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Showing 1-20 of about 20 results.
Resolution-dependent subsonic non-thermal line dispersion revealed by ALMAYue, Nan-NanLi, DiZhang, Qi-ZhouZhu, LeiHenshaw, JonathanMardones, DiegoRen, Zhi-YuanDOI: info:10.1088/1674-4527/21/1/24v. 21024
Yue, Nan-Nan, Li, Di, Zhang, Qi-Zhou, Zhu, Lei, Henshaw, Jonathan, Mardones, Diego, and Ren, Zhi-Yuan. 2021. "Resolution-dependent subsonic non-thermal line dispersion revealed by ALMA." Research in Astronomy and Astrophysics 21:024. https://doi.org/10.1088/1674-4527/21/1/24
ID: 159435
Type: article
Authors: Yue, Nan-Nan; Li, Di; Zhang, Qi-Zhou; Zhu, Lei; Henshaw, Jonathan; Mardones, Diego; Ren, Zhi-Yuan
Abstract: We report here Atacama Large Millimeter/submillimeter Array (ALMA) N2H+ (1-0) images of the Orion Molecular Cloud 2 and 3 (OMC-2/3) with high angular resolution (3″ or 1200 au) and high spatial dynamic range. Combining a dataset from the ALMA main array, Atacama Compact Array (ACA), Nobeyama 45-m Telescope and Very Large Array (VLA) (providing temperature measurement on matching scales), we find that most of the dense gas in OMC-2/3 is subsonic (σNT / Cs = 0.62) with a mean line width (Δυ) of 0.39 km s-1 full width at half maximum (FWHM). This is markedly different from the majority of previous observations of massive star-forming regions. In contrast, line widths from the Nobeyama Telescope are transonic at 0.69 km s-1 (σNT / Cs = 1.08). We demonstrated that the larger line widths obtained by the single-dish telescope arose from unresolved sub-structures within their respective beams. The dispersions from larger scales σls (as traced by the Nobeyama Telescope) can be decomposed into three components such that ${\sigma }_{{\rm{ls}}}^{2}={\sigma }_{{\rm{ss}}}^{2}+{\sigma }_{{\rm{bm}}}^{2}+{\sigma }_{{\rm{rd}}}^{2}$ , where small-scale σss is the line dispersion of each ALMA beam, bulk motion σbm is dispersion between peak velocity of each ALMA beam and σrd is the residual dispersion. Such decomposition, though purely empirical, appears to be robust throughout our data cubes. Apparent supersonic line widths, commonly found in massive molecular clouds, are thus likely due to the effect of poor spatial resolution. The observed non-thermal line dispersion (sometimes referred to as 'turbulence') transits from supersonic to subsonic at ∼ 0.05 pc scales in the OMC-2/3 region. Such transition could be commonly found with sufficient spatial (not just angular) resolution, even in regions with massive young clusters, such as the Orion molecular clouds studied here.
Type: article
Authors: Yue, Nan-Nan; Li, Di; Zhang, Qi-Zhou; Zhu, Lei; Henshaw, Jonathan; Mardones, Diego; Ren, Zhi-Yuan
Abstract: We report here Atacama Large Millimeter/submillimeter Array (ALMA) N2H+ (1-0) images of the Orion Molecular Cloud 2 and 3 (OMC-2/3) with high angular resolution (3″ or 1200 au) and high spatial dynamic range. Combining a dataset from the ALMA main array, Atacama Compact Array (ACA), Nobeyama 45-m Telescope and Very Large Array (VLA) (providing temperature measurement on matching scales), we find that most of the dense gas in OMC-2/3 is subsonic (σNT / Cs = 0.62) with a mean line width (Δυ) of 0.39 km s-1 full width at half maximum (FWHM). This is markedly different from the majority of previous observations of massive star-forming regions. In contrast, line widths from the Nobeyama Telescope are transonic at 0.69 km s-1 (σNT / Cs = 1.08). We demonstrated that the larger line widths obtained by the single-dish telescope arose from unresolved sub-structures within their respective beams. The dispersions from larger scales σls (as traced by the Nobeyama Telescope) can be decomposed into three components such that ${\sigma }_{{\rm{ls}}}^{2}={\sigma }_{{\rm{ss}}}^{2}+{\sigma }_{{\rm{bm}}}^{2}+{\sigma }_{{\rm{rd}}}^{2}$ , where small-scale σss is the line dispersion of each ALMA beam, bulk motion σbm is dispersion between peak velocity of each ALMA beam and σrd is the residual dispersion. Such decomposition, though purely empirical, appears to be robust throughout our data cubes. Apparent supersonic line widths, commonly found in massive molecular clouds, are thus likely due to the effect of poor spatial resolution. The observed non-thermal line dispersion (sometimes referred to as 'turbulence') transits from supersonic to subsonic at ∼ 0.05 pc scales in the OMC-2/3 region. Such transition could be commonly found with sufficient spatial (not just angular) resolution, even in regions with massive young clusters, such as the Orion molecular clouds studied here.
Development of the global atmospheric chemistry general circulation model BCC-GEOS-Chem v1.0: model description and evaluationLu, XiaoZhang, LinWu, TongwenLong, Michael S.Wang, JunJacob, Daniel J.Zhang, FangZhang, JieEastham, Sebastian D.Hu, LuZhu, LeiLiu, XiongWei, MinDOI: info:10.5194/gmd-13-3817-2020v. 133817–3838
Lu, Xiao, Zhang, Lin, Wu, Tongwen, Long, Michael S., Wang, Jun, Jacob, Daniel J., Zhang, Fang, Zhang, Jie, Eastham, Sebastian D., Hu, Lu, Zhu, Lei, Liu, Xiong, and Wei, Min. 2020. "Development of the global atmospheric chemistry general circulation model BCC-GEOS-Chem v1.0: model description and evaluation." Geoscientific Model Development 13:3817– 3838. https://doi.org/10.5194/gmd-13-3817-2020
ID: 157462
Type: article
Authors: Lu, Xiao; Zhang, Lin; Wu, Tongwen; Long, Michael S.; Wang, Jun; Jacob, Daniel J.; Zhang, Fang; Zhang, Jie; Eastham, Sebastian D.; Hu, Lu; Zhu, Lei; Liu, Xiong; Wei, Min
Abstract: Chemistry plays an indispensable role in investigations of the atmosphere; however, many climate models either ignore or greatly simplify atmospheric chemistry, limiting both their accuracy and their scope. We present the development and evaluation of the online global atmospheric chemical model BCC-GEOS-Chem v1.0, coupling the GEOS-Chem chemical transport model (CTM) as an atmospheric chemistry component in the Beijing Climate Center atmospheric general circulation model (BCC-AGCM). The GEOS-Chem atmospheric chemistry component includes detailed tropospheric HOx-NOx-volatile organic compounds-ozone-bromine-aerosol chemistry and online dry and wet deposition schemes. We then demonstrate the new capabilities of BCC-GEOS-Chem v1.0 relative to the base BCC-AGCM model through a 3-year (2012-2014) simulation with anthropogenic emissions from the Community Emissions Data System (CEDS) used in the Coupled Model Intercomparison Project Phase 6 (CMIP6). The model captures well the spatial distributions and seasonal variations in tropospheric ozone, with seasonal mean biases of 0.4-2.2 ppbv at 700-400 hPa compared to satellite observations and within 10 ppbv at the surface to 500 hPa compared to global ozonesonde observations. The model has larger high-ozone biases over the tropics which we attribute to an overestimate of ozone chemical production. It underestimates ozone in the upper troposphere which is likely due either to the use of a simplified stratospheric ozone scheme or to biases in estimated stratosphere-troposphere exchange dynamics. The model diagnoses the global tropospheric ozone burden, OH concentration, and methane chemical lifetime to be 336 Tg, 1.16×106 molecule cm-3, and 8.3 years, respectively, which is consistent with recent multimodel assessments. The spatiotemporal distributions of NO2, CO, SO2, CH2O, and aerosol optical depth are generally in agreement with satellite observations. The development of BCC-GEOS-Chem v1.0 represents an important step for the development of fully coupled earth system models (ESMs) in China.
Type: article
Authors: Lu, Xiao; Zhang, Lin; Wu, Tongwen; Long, Michael S.; Wang, Jun; Jacob, Daniel J.; Zhang, Fang; Zhang, Jie; Eastham, Sebastian D.; Hu, Lu; Zhu, Lei; Liu, Xiong; Wei, Min
Abstract: Chemistry plays an indispensable role in investigations of the atmosphere; however, many climate models either ignore or greatly simplify atmospheric chemistry, limiting both their accuracy and their scope. We present the development and evaluation of the online global atmospheric chemical model BCC-GEOS-Chem v1.0, coupling the GEOS-Chem chemical transport model (CTM) as an atmospheric chemistry component in the Beijing Climate Center atmospheric general circulation model (BCC-AGCM). The GEOS-Chem atmospheric chemistry component includes detailed tropospheric HOx-NOx-volatile organic compounds-ozone-bromine-aerosol chemistry and online dry and wet deposition schemes. We then demonstrate the new capabilities of BCC-GEOS-Chem v1.0 relative to the base BCC-AGCM model through a 3-year (2012-2014) simulation with anthropogenic emissions from the Community Emissions Data System (CEDS) used in the Coupled Model Intercomparison Project Phase 6 (CMIP6). The model captures well the spatial distributions and seasonal variations in tropospheric ozone, with seasonal mean biases of 0.4-2.2 ppbv at 700-400 hPa compared to satellite observations and within 10 ppbv at the surface to 500 hPa compared to global ozonesonde observations. The model has larger high-ozone biases over the tropics which we attribute to an overestimate of ozone chemical production. It underestimates ozone in the upper troposphere which is likely due either to the use of a simplified stratospheric ozone scheme or to biases in estimated stratosphere-troposphere exchange dynamics. The model diagnoses the global tropospheric ozone burden, OH concentration, and methane chemical lifetime to be 336 Tg, 1.16×106 molecule cm-3, and 8.3 years, respectively, which is consistent with recent multimodel assessments. The spatiotemporal distributions of NO2, CO, SO2, CH2O, and aerosol optical depth are generally in agreement with satellite observations. The development of BCC-GEOS-Chem v1.0 represents an important step for the development of fully coupled earth system models (ESMs) in China.
An inversion of NOx and non-methane volatile organic compound (NMVOC) emissions using satellite observations during the KORUS-AQ campaign and implications for surface ozone over East AsiaSouri, Amir H.Nowlan, Caroline R.González Abad, GonzaloZhu, LeiBlake, Donald R.Fried, AlanWeinheimer, Andrew J.Wisthaler, ArminWoo, Jung-HunZhang, QiangMiller, Christopher E. ChanLiu, XiongChance, KellyDOI: info:10.5194/acp-20-9837-2020v. 209837–9854
Souri, Amir H., Nowlan, Caroline R., González Abad, Gonzalo, Zhu, Lei, Blake, Donald R., Fried, Alan, Weinheimer, Andrew J., Wisthaler, Armin, Woo, Jung-Hun, Zhang, Qiang, Miller, Christopher E. Chan, Liu, Xiong, and Chance, Kelly. 2020. "An inversion of NOx and non-methane volatile organic compound (NMVOC) emissions using satellite observations during the KORUS-AQ campaign and implications for surface ozone over East Asia." Atmospheric Chemistry & Physics 20:9837– 9854. https://doi.org/10.5194/acp-20-9837-2020
ID: 158080
Type: article
Authors: Souri, Amir H.; Nowlan, Caroline R.; González Abad, Gonzalo; Zhu, Lei; Blake, Donald R.; Fried, Alan; Weinheimer, Andrew J.; Wisthaler, Armin; Woo, Jung-Hun; Zhang, Qiang; Miller, Christopher E. Chan; Liu, Xiong; Chance, Kelly
Abstract: The absence of up-to-date emissions has been a major impediment to accurately simulating aspects of atmospheric chemistry and to precisely quantifying the impact of changes in emissions on air pollution. Hence, a nonlinear joint analytical inversion (Gauss-Newton method) of both volatile organic compounds (VOCs) and nitrogen oxide (NOx) emissions is made by exploiting the Smithsonian Astrophysical Observatory (SAO) Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) formaldehyde (HCHO) and the National Aeronautics and Space Administration (NASA) Ozone Monitoring Instrument (OMI) tropospheric nitrogen dioxide (NO2) columns during the Korea-United States Air Quality (KORUS-AQ) campaign over East Asia in May-June 2016. Effects of the chemical feedback of NOx and VOCs on both NO2 and HCHO are implicitly included by iteratively optimizing the inversion. Emission uncertainties are greatly narrowed (averaging kernels > 0.8, which is the mathematical presentation of the partition of information gained from the satellite observations with respect to the prior knowledge) over medium- to high-emitting areas such as cities and dense vegetation. The prior amount of total NOx emissions is mainly dictated by values reported in the MIX-Asia 2010 inventory. After the inversion we conclude that there is a decline in emissions (before, after, change) for China (87.94±44.09 Gg d-1, 68.00±15.94 Gg d-1, -23 %), North China Plain (NCP) (27.96±13.49 Gg d-1, 19.05±2.50 Gg d-1, -32 %), Pearl River Delta (PRD) (4.23±1.78 Gg d-1, 2.70±0.32 Gg d-1, -36 %), Yangtze River Delta (YRD) (9.84±4.68 Gg d-1, 5.77±0.51 Gg d-1, -41 %), Taiwan (1.26±0.57 Gg d-1, 0.97±0.33 Gg d-1, -23 %), and Malaysia (2.89±2.77 Gg d-1, 2.25±1.34 Gg d-1, -22 %), all of which have effectively implemented various stringent regulations. In contrast, South Korea (2.71±1.34 Gg d-1, 2.95±0.58 Gg d-1, +9 %) and Japan (3.53±1.71 Gg d-1, 3.96±1.04 Gg d-1, +12 %) are experiencing an increase in NOx emissions, potentially due to an increased number of diesel vehicles and new thermal power plants. We revisit the well-documented positive bias (by a factor of 2 to 3) of MEGAN v2.1 (Model of Emissions of Gases and Aerosols from Nature) in terms of biogenic VOC emissions in the tropics. The inversion, however, suggests a larger growth of VOCs (mainly anthropogenic) over NCP (25 %) than previously reported (6 %) relative to 2010. The spatial variation in both the magnitude and sign of NOx and VOC emissions results in nonlinear responses of ozone production and loss. Due to a simultaneous decrease and increase in NOx/VOC over NCP and YRD, we observe a ∼53 % reduction in the ratio of the chemical loss of NOx (LNOx) to the chemical loss of ROx (RO2+HO2) over the surface transitioning toward NOx-sensitive regimes, which in turn reduces and increases the afternoon chemical loss and production of ozone through NO2+OH (-0.42 ppbv h-1)/HO2 (and RO2)+NO (+0.31 ppbv h-1). Conversely, a combined decrease in NOx and VOC emissions in Taiwan, Malaysia, and southern China suppresses the formation of ozone. Simulations using the updated emissions indicate increases in maximum daily 8 h average (MDA8) surface ozone over China (0.62 ppbv), NCP (4.56 ppbv), and YRD (5.25 ppbv), suggesting that emission control strategies on VOCs should be prioritized to curb ozone production rates in these regions. Taiwan, Malaysia, and PRD stand out as regions undergoing lower MDA8 ozone levels resulting from the NOx reductions occurring predominantly in NOx-sensitive regimes.
Type: article
Authors: Souri, Amir H.; Nowlan, Caroline R.; González Abad, Gonzalo; Zhu, Lei; Blake, Donald R.; Fried, Alan; Weinheimer, Andrew J.; Wisthaler, Armin; Woo, Jung-Hun; Zhang, Qiang; Miller, Christopher E. Chan; Liu, Xiong; Chance, Kelly
Abstract: The absence of up-to-date emissions has been a major impediment to accurately simulating aspects of atmospheric chemistry and to precisely quantifying the impact of changes in emissions on air pollution. Hence, a nonlinear joint analytical inversion (Gauss-Newton method) of both volatile organic compounds (VOCs) and nitrogen oxide (NOx) emissions is made by exploiting the Smithsonian Astrophysical Observatory (SAO) Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) formaldehyde (HCHO) and the National Aeronautics and Space Administration (NASA) Ozone Monitoring Instrument (OMI) tropospheric nitrogen dioxide (NO2) columns during the Korea-United States Air Quality (KORUS-AQ) campaign over East Asia in May-June 2016. Effects of the chemical feedback of NOx and VOCs on both NO2 and HCHO are implicitly included by iteratively optimizing the inversion. Emission uncertainties are greatly narrowed (averaging kernels > 0.8, which is the mathematical presentation of the partition of information gained from the satellite observations with respect to the prior knowledge) over medium- to high-emitting areas such as cities and dense vegetation. The prior amount of total NOx emissions is mainly dictated by values reported in the MIX-Asia 2010 inventory. After the inversion we conclude that there is a decline in emissions (before, after, change) for China (87.94±44.09 Gg d-1, 68.00±15.94 Gg d-1, -23 %), North China Plain (NCP) (27.96±13.49 Gg d-1, 19.05±2.50 Gg d-1, -32 %), Pearl River Delta (PRD) (4.23±1.78 Gg d-1, 2.70±0.32 Gg d-1, -36 %), Yangtze River Delta (YRD) (9.84±4.68 Gg d-1, 5.77±0.51 Gg d-1, -41 %), Taiwan (1.26±0.57 Gg d-1, 0.97±0.33 Gg d-1, -23 %), and Malaysia (2.89±2.77 Gg d-1, 2.25±1.34 Gg d-1, -22 %), all of which have effectively implemented various stringent regulations. In contrast, South Korea (2.71±1.34 Gg d-1, 2.95±0.58 Gg d-1, +9 %) and Japan (3.53±1.71 Gg d-1, 3.96±1.04 Gg d-1, +12 %) are experiencing an increase in NOx emissions, potentially due to an increased number of diesel vehicles and new thermal power plants. We revisit the well-documented positive bias (by a factor of 2 to 3) of MEGAN v2.1 (Model of Emissions of Gases and Aerosols from Nature) in terms of biogenic VOC emissions in the tropics. The inversion, however, suggests a larger growth of VOCs (mainly anthropogenic) over NCP (25 %) than previously reported (6 %) relative to 2010. The spatial variation in both the magnitude and sign of NOx and VOC emissions results in nonlinear responses of ozone production and loss. Due to a simultaneous decrease and increase in NOx/VOC over NCP and YRD, we observe a ∼53 % reduction in the ratio of the chemical loss of NOx (LNOx) to the chemical loss of ROx (RO2+HO2) over the surface transitioning toward NOx-sensitive regimes, which in turn reduces and increases the afternoon chemical loss and production of ozone through NO2+OH (-0.42 ppbv h-1)/HO2 (and RO2)+NO (+0.31 ppbv h-1). Conversely, a combined decrease in NOx and VOC emissions in Taiwan, Malaysia, and southern China suppresses the formation of ozone. Simulations using the updated emissions indicate increases in maximum daily 8 h average (MDA8) surface ozone over China (0.62 ppbv), NCP (4.56 ppbv), and YRD (5.25 ppbv), suggesting that emission control strategies on VOCs should be prioritized to curb ozone production rates in these regions. Taiwan, Malaysia, and PRD stand out as regions undergoing lower MDA8 ozone levels resulting from the NOx reductions occurring predominantly in NOx-sensitive regimes.
Filament intersections and cold dense cores in Orion A NorthZhang, ChaoRen, ZhiyuanWu, JingwenLi, DiZhu, LeiZhang, QizhouMardones, DiegoWang, ChenShi, HuiYue, NannanLuo, GanXie, JinjinJiao, SihanLiu, ShuXu, XuefangWang, ShenDOI: info:10.1093/mnras/staa1958v. 497793–808
Zhang, Chao, Ren, Zhiyuan, Wu, Jingwen, Li, Di, Zhu, Lei, Zhang, Qizhou, Mardones, Diego, Wang, Chen, Shi, Hui, Yue, Nannan, Luo, Gan, Xie, Jinjin, Jiao, Sihan, Liu, Shu, Xu, Xuefang, and Wang, Shen. 2020. "Filament intersections and cold dense cores in Orion A North." Monthly Notices of the Royal Astronomical Society 497:793– 808. https://doi.org/10.1093/mnras/staa1958
ID: 158748
Type: article
Authors: Zhang, Chao; Ren, Zhiyuan; Wu, Jingwen; Li, Di; Zhu, Lei; Zhang, Qizhou; Mardones, Diego; Wang, Chen; Shi, Hui; Yue, Nannan; Luo, Gan; Xie, Jinjin; Jiao, Sihan; Liu, Shu; Xu, Xuefang; Wang, Shen
Abstract: We studied the filament structures and cold dense cores in OMC-2,3 region in Orion A North molecular cloud using the high-resolution N2H+ (1-0) spectral cube observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). The filament network over a total length of 2 pc is found to contain 170 intersections and 128 candidate dense cores. The dense cores are all displaced from the infrared point sources (possible young stars), and the major fraction of cores (103) are located around the intersections. Towards the intersections, there is also an increasing trend for the total column density Ntot as well as the power-law index of the column-density Probability Distribution Function (N-PDF), suggesting that the intersections would in general have more significant gas assembly than the other part of the filament paths. The virial analysis shows that the dense cores mostly have virial mass ratio of avir = Mvir/Mgas crit = Mcrit/Mgas < 1.0, suggesting them to be unstable against core collapse. Combining these results, it shows that the major fraction of the cold starless and possible pre-stellar cores in OMC-2,3 are being assembled around the intersections, and currently in a gravitationally bound state. But more extensive core-collapse and star formation may still require continuous core mass growth or other perturbations.
Type: article
Authors: Zhang, Chao; Ren, Zhiyuan; Wu, Jingwen; Li, Di; Zhu, Lei; Zhang, Qizhou; Mardones, Diego; Wang, Chen; Shi, Hui; Yue, Nannan; Luo, Gan; Xie, Jinjin; Jiao, Sihan; Liu, Shu; Xu, Xuefang; Wang, Shen
Abstract: We studied the filament structures and cold dense cores in OMC-2,3 region in Orion A North molecular cloud using the high-resolution N2H+ (1-0) spectral cube observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). The filament network over a total length of 2 pc is found to contain 170 intersections and 128 candidate dense cores. The dense cores are all displaced from the infrared point sources (possible young stars), and the major fraction of cores (103) are located around the intersections. Towards the intersections, there is also an increasing trend for the total column density Ntot as well as the power-law index of the column-density Probability Distribution Function (N-PDF), suggesting that the intersections would in general have more significant gas assembly than the other part of the filament paths. The virial analysis shows that the dense cores mostly have virial mass ratio of avir = Mvir/Mgas crit = Mcrit/Mgas < 1.0, suggesting them to be unstable against core collapse. Combining these results, it shows that the major fraction of the cold starless and possible pre-stellar cores in OMC-2,3 are being assembled around the intersections, and currently in a gravitationally bound state. But more extensive core-collapse and star formation may still require continuous core mass growth or other perturbations.
Validation of satellite formaldehyde (HCHO) retrievals using observations from 12 aircraft campaignsZhu, LeiAbad, Gonzalo GonzalezNowlan, Caroline R.Miller, Christopher ChanChance, KellyApel, Eric C.DiGangi, Joshua P.Fried, AlanHanisco, Thomas F.Hornbrook, Rebecca S.Hu, LuKaiser, JenniferKeutsch, Frank N.Permar, WadeSt Clair, Jason M.Wolfe, Glenn M.DOI: info:10.5194/acp-20-12329-2020v. 20No. 2012329–12345
Zhu, Lei, Abad, Gonzalo Gonzalez, Nowlan, Caroline R., Miller, Christopher Chan, Chance, Kelly, Apel, Eric C., DiGangi, Joshua P., Fried, Alan, Hanisco, Thomas F., Hornbrook, Rebecca S., Hu, Lu, Kaiser, Jennifer, Keutsch, Frank N., Permar, Wade, St Clair, Jason M., and Wolfe, Glenn M. 2020. "Validation of satellite formaldehyde (HCHO) retrievals using observations from 12 aircraft campaigns." Atmospheric Chemistry and Physics 20 (20):12329– 12345. https://doi.org/10.5194/acp-20-12329-2020
ID: 157528
Type: article
Authors: Zhu, Lei; Abad, Gonzalo Gonzalez; Nowlan, Caroline R.; Miller, Christopher Chan; Chance, Kelly; Apel, Eric C.; DiGangi, Joshua P.; Fried, Alan; Hanisco, Thomas F.; Hornbrook, Rebecca S.; Hu, Lu; Kaiser, Jennifer; Keutsch, Frank N.; Permar, Wade; St Clair, Jason M.; Wolfe, Glenn M.
Abstract: Formaldehyde (HCHO) has been measured from space for more than 2 decades. Owing to its short atmospheric lifetime, satellite HCHO data are used widely as a proxy of volatile organic compounds (VOCs; please refer to Appendix A for abbreviations and acronyms), providing constraints on underlying emissions and chemistry. However, satellite HCHO products from different satellite sensors using different algorithms have received little validation so far. The accuracy and consistency of HCHO retrievals remain largely unclear. Here we develop a validation platform for satellite HCHO retrievals using in situ observations from 12 aircraft campaigns with a chemical transport model (GEOS-Chem) as the intercomparison method. Application to the NASA operational OMI HCHO product indicates negative biases (- 44.5 % to -21.7 %) under high-HCHO conditions, while it indicates high biases (+66.1 % to +112.1 %) under low-HCHO conditions. Under both conditions, HCHO a priori vertical profiles are likely not the main driver of the biases. By providing quick assessment of systematic biases in satellite products over large domains, the platform facilitates, in an iterative process, optimization of retrieval settings and the minimization of retrieval biases. It is also complementary to localized validation efforts based on ground observations and aircraft spirals.
Type: article
Authors: Zhu, Lei; Abad, Gonzalo Gonzalez; Nowlan, Caroline R.; Miller, Christopher Chan; Chance, Kelly; Apel, Eric C.; DiGangi, Joshua P.; Fried, Alan; Hanisco, Thomas F.; Hornbrook, Rebecca S.; Hu, Lu; Kaiser, Jennifer; Keutsch, Frank N.; Permar, Wade; St Clair, Jason M.; Wolfe, Glenn M.
Abstract: Formaldehyde (HCHO) has been measured from space for more than 2 decades. Owing to its short atmospheric lifetime, satellite HCHO data are used widely as a proxy of volatile organic compounds (VOCs; please refer to Appendix A for abbreviations and acronyms), providing constraints on underlying emissions and chemistry. However, satellite HCHO products from different satellite sensors using different algorithms have received little validation so far. The accuracy and consistency of HCHO retrievals remain largely unclear. Here we develop a validation platform for satellite HCHO retrievals using in situ observations from 12 aircraft campaigns with a chemical transport model (GEOS-Chem) as the intercomparison method. Application to the NASA operational OMI HCHO product indicates negative biases (- 44.5 % to -21.7 %) under high-HCHO conditions, while it indicates high biases (+66.1 % to +112.1 %) under low-HCHO conditions. Under both conditions, HCHO a priori vertical profiles are likely not the main driver of the biases. By providing quick assessment of systematic biases in satellite products over large domains, the platform facilitates, in an iterative process, optimization of retrieval settings and the minimization of retrieval biases. It is also complementary to localized validation efforts based on ground observations and aircraft spirals.
The JCMT BISTRO Survey: The Magnetic Field of the Barnard 1 Star-forming RegionCoudé, SimonBastien, PierreHoude, MartinSadavoy, SarahFriesen, Racheldi Francesco, JamesJohnstone, DougMairs, SteveHasegawa, TetsuoKwon, WoojinLai, Shih-PingQiu, KepingWard-Thompson, DerekBerry, DavidChen, Michael Chun-YuanFiege, JasonFranzmann, EricaHatchell, JenniferLacaille, KevinMatthews, Brenda C.Moriarty-Schieven, Gerald H.Pon, AndyAndré, PhilippeArzoumanian, DorisAso, YusukeByun, Do-YoungEswaraiah, ChakaliChen, Huei-RuChen, Wen PingChing, Tao-ChungCho, JungyeonChoi, MinhoChrysostomou, AntonioChung, Eun JungDoi, YasuoDrabek-Maunder, EmilyDowell, C. DarrenEyres, Stewart P. S.Falle, SamFriberg, PerFuller, GaryFuruya, Ray S.Gledhill, TimGraves, Sarah F.Greaves, Jane S.Griffin, Matt J.Gu, QilaoHayashi, Saeko S.Hoang, ThiemHolland, WayneInoue, TsuyoshiInutsuka, Shu-ichiroIwasaki, KazunariJeong, Il-GyoKanamori, YoshihiroKataoka, AkimasaKang, Ji-hyunKang, MijuKang, Sung-juKawabata, Koji S.Kemper, FranciscaKim, GwanjeongKim, JongsooKim, Kee-TaeKim, Kyoung HeeKim, Mi-RyangKim, ShinyoungKirk, Jason M.Kobayashi, Masato I. N.Koch, Patrick M.Kwon, JungmiLee, Jeong-EunLee, Chang WonLee, Sang-SungLi, DaleiLi, DiLi, Hua-BaiLiu, Hong-LiLiu, JunhaoLiu, Sheng-YuanLiu, TieVan Loo, SvenLyo, A. -RanMatsumura, MasafumiNagata, TetsuyaNakamura, FumitakaNakanishi, HiroyukiOhashi, NagayoshiOnaka, TakashiParsons, HarrietPattle, KatePeretto, NicolasPyo, Tae-SooQian, LeiRao, RamprasadRawlings, Mark G.Retter, BrendanRicher, JohnRigby, AndrewRobitaille, Jean-FrançoisSaito, HiroSavini, GiorgioScaife, Anna M. M.Seta, MasumichiShinnaga, HirokoSoam, ArchanaTamura, MotohideTang, Ya-WenTomisaka, KohjiTsukamoto, YusukeWang, HongchiWang, Jia-WeiWhitworth, Anthony P.Yen, Hsi-WeiYoo, HyunjuYuan, JinghuaZenko, TetsuyaZhang, Chuan-PengZhang, GuoyinZhou, JianjunZhu, LeiThe B-fields In STar-forming Regions Observations (BISTRO CollaborationDOI: info:10.3847/1538-4357/ab1b23v. 87788
Coudé, Simon, Bastien, Pierre, Houde, Martin, Sadavoy, Sarah, Friesen, Rachel, di Francesco, James, Johnstone, Doug, Mairs, Steve, Hasegawa, Tetsuo, Kwon, Woojin, Lai, Shih-Ping, Qiu, Keping, Ward-Thompson, Derek, Berry, David, Chen, Michael Chun-Yuan, Fiege, Jason, Franzmann, Erica, Hatchell, Jennifer, Lacaille, Kevin, Matthews, Brenda C., Moriarty-Schieven, Gerald H., Pon, Andy, André, Philippe, Arzoumanian, Doris, Aso, Yusuke et al. 2019. "The JCMT BISTRO Survey: The Magnetic Field of the Barnard 1 Star-forming Region." The Astrophysical Journal 877:88. https://doi.org/10.3847/1538-4357/ab1b23
ID: 152904
Type: article
Authors: Coudé, Simon; Bastien, Pierre; Houde, Martin; Sadavoy, Sarah; Friesen, Rachel; di Francesco, James; Johnstone, Doug; Mairs, Steve; Hasegawa, Tetsuo; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Ward-Thompson, Derek; Berry, David; Chen, Michael Chun-Yuan; Fiege, Jason; Franzmann, Erica; Hatchell, Jennifer; Lacaille, Kevin; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Pon, Andy; André, Philippe; Arzoumanian, Doris; Aso, Yusuke; Byun, Do-Young; Eswaraiah, Chakali; Chen, Huei-Ru; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Dowell, C. Darren; Eyres, Stewart P. S.; Falle, Sam; Friberg, Per; Fuller, Gary; Furuya, Ray S.; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Gu, Qilao; Hayashi, Saeko S.; Hoang, Thiem; Holland, Wayne; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kanamori, Yoshihiro; Kataoka, Akimasa; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Koch, Patrick M.; Kwon, Jungmi; Lee, Jeong-Eun; Lee, Chang Won; Lee, Sang-Sung; Li, Dalei; Li, Di; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Liu, Sheng-Yuan; Liu, Tie; Van Loo, Sven; Lyo, A. -Ran; Matsumura, Masafumi; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Parsons, Harriet; Pattle, Kate; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Soam, Archana; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zenko, Tetsuya; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; The B-fields In STar-forming Regions Observations (BISTRO Collaboration
Abstract: We present the POL-2 850 μm linear polarization map of the Barnard 1 clump in the Perseus molecular cloud complex from the B-fields In STar-forming Region Observations survey at the James Clerk Maxwell Telescope. We find a trend of decreasing polarization fraction as a function of total intensity, which we link to depolarization effects toward higher-density regions of the cloud. We then use the polarization data at 850 μm to infer the plane-of-sky orientation of the large-scale magnetic field in Barnard 1. This magnetic field runs north–south across most of the cloud, with the exception of B1-c, where it turns more east–west. From the dispersion of polarization angles, we calculate a turbulence correlation length of 5.0 ± 2.″5 (1500 au) and a turbulent-to-total magnetic energy ratio of 0.5 ± 0.3 inside the cloud. We combine this turbulent-to-total magnetic energy ratio with observations of NH3 molecular lines from the Green Bank Ammonia Survey to estimate the strength of the plane-of-sky component of the magnetic field through the Davis–Chandrasekhar–Fermi method. With a plane-of-sky amplitude of 120 ± 60 μG and a criticality criterion λ c = 3.0 ± 1.5, we find that Barnard 1 is a supercritical molecular cloud with a magnetic field nearly dominated by its turbulent component.
Type: article
Authors: Coudé, Simon; Bastien, Pierre; Houde, Martin; Sadavoy, Sarah; Friesen, Rachel; di Francesco, James; Johnstone, Doug; Mairs, Steve; Hasegawa, Tetsuo; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Ward-Thompson, Derek; Berry, David; Chen, Michael Chun-Yuan; Fiege, Jason; Franzmann, Erica; Hatchell, Jennifer; Lacaille, Kevin; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Pon, Andy; André, Philippe; Arzoumanian, Doris; Aso, Yusuke; Byun, Do-Young; Eswaraiah, Chakali; Chen, Huei-Ru; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Dowell, C. Darren; Eyres, Stewart P. S.; Falle, Sam; Friberg, Per; Fuller, Gary; Furuya, Ray S.; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Gu, Qilao; Hayashi, Saeko S.; Hoang, Thiem; Holland, Wayne; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kanamori, Yoshihiro; Kataoka, Akimasa; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Koch, Patrick M.; Kwon, Jungmi; Lee, Jeong-Eun; Lee, Chang Won; Lee, Sang-Sung; Li, Dalei; Li, Di; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Liu, Sheng-Yuan; Liu, Tie; Van Loo, Sven; Lyo, A. -Ran; Matsumura, Masafumi; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Parsons, Harriet; Pattle, Kate; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Soam, Archana; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zenko, Tetsuya; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; The B-fields In STar-forming Regions Observations (BISTRO Collaboration
Abstract: We present the POL-2 850 μm linear polarization map of the Barnard 1 clump in the Perseus molecular cloud complex from the B-fields In STar-forming Region Observations survey at the James Clerk Maxwell Telescope. We find a trend of decreasing polarization fraction as a function of total intensity, which we link to depolarization effects toward higher-density regions of the cloud. We then use the polarization data at 850 μm to infer the plane-of-sky orientation of the large-scale magnetic field in Barnard 1. This magnetic field runs north–south across most of the cloud, with the exception of B1-c, where it turns more east–west. From the dispersion of polarization angles, we calculate a turbulence correlation length of 5.0 ± 2.″5 (1500 au) and a turbulent-to-total magnetic energy ratio of 0.5 ± 0.3 inside the cloud. We combine this turbulent-to-total magnetic energy ratio with observations of NH3 molecular lines from the Green Bank Ammonia Survey to estimate the strength of the plane-of-sky component of the magnetic field through the Davis–Chandrasekhar–Fermi method. With a plane-of-sky amplitude of 120 ± 60 μG and a criticality criterion λ c = 3.0 ± 1.5, we find that Barnard 1 is a supercritical molecular cloud with a magnetic field nearly dominated by its turbulent component.
The JCMT BISTRO Survey: The Magnetic Field in the Starless Core ρ Ophiuchus CLiu, JunhaoQiu, KepingBerry, Daviddi Francesco, JamesBastien, PierreKoch, Patrick M.Furuya, Ray S.Kim, Kee-TaeCoudé, SimonLee, Chang WonSoam, ArchanaEswaraiah, ChakaliLi, DiHwang, JihyeLyo, A. -RanPattle, KateHasegawa, TetsuoKwon, WoojinLai, Shih-PingWard-Thompson, DerekChing, Tao-ChungChen, ZhiweiGu, QilaoLi, DaleiLi, Hua-BaiLiu, Hong-LiQian, LeiWang, HongchiYuan, JinghuaZhang, Chuan-PengZhang, GuoyinZhang, Ya-PengZhou, JianjunZhu, LeiAndré, PhilippeArzoumanian, DorisAso, YusukeByun, Do-YoungChen, Michael Chun-YuanChen, Huei-Ru VivienChen, Wen PingCho, JungyeonChoi, MinhoChrysostomou, AntonioChung, Eun JungDoi, YasuoDrabek-Maunder, EmilyDowell, C. DarrenEyres, Stewart P. S.Falle, SamFanciullo, LapoFiege, JasonFranzmann, EricaFriberg, PerFriesen, Rachel K.Fuller, GaryGledhill, TimGraves, Sarah F.Greaves, Jane S.Griffin, Matt J.Han, IlseungHatchell, JenniferHayashi, Saeko S.Hoang, ThiemHolland, WayneHoude, MartinInoue, TsuyoshiInutsuka, Shu-ichiroIwasaki, KazunariJeong, Il-GyoJohnstone, DougKanamori, YoshihiroKang, Ji-hyunKang, MijuKang, Sung-juKataoka, AkimasaKawabata, Koji S.Kemper, FranciscaKim, GwanjeongKim, JongsooKim, Kyoung HeeKim, Mi-RyangKim, ShinyoungKirk, Jason M.Kobayashi, Masato I. N.Kusune, TakayoshiKwon, JungmiLacaille, Kevin M.Lee, Chin-FeiLee, Jeong-EunLee, HyeseungLee, Sang-SungLiu, Sheng-YuanLiu, TieVan Loo, SvenMairs, SteveMatsumura, MasafumiMatthews, Brenda C.Moriarty-Schieven, Gerald H.Nagata, TetsuyaNakamura, FumitakaNakanishi, HiroyukiOhashi, NagayoshiOnaka, TakashiParker, JoshParsons, HarrietPascale, EnzoPeretto, NicolasPon, AndyPyo, Tae-SooRao, RamprasadRawlings, Mark G.Retter, BrendanRicher, JohnRigby, AndrewRobitaille, Jean-FrançoisSadavoy, SarahSaito, HiroSavini, GiorgioScaife, Anna M. M.Seta, MasumichiShinnaga, HirokoTamura, MotohideTang, Ya-WenTomisaka, KohjiTsukamoto, YusukeWang, Jia-WeiWhitworth, Anthony P.Yen, Hsi-WeiYoo, HyunjuZenko, TetsuyaDOI: info:10.3847/1538-4357/ab0958v. 87743
Liu, Junhao, Qiu, Keping, Berry, David, di Francesco, James, Bastien, Pierre, Koch, Patrick M., Furuya, Ray S., Kim, Kee-Tae, Coudé, Simon, Lee, Chang Won, Soam, Archana, Eswaraiah, Chakali, Li, Di, Hwang, Jihye, Lyo, A. -Ran, Pattle, Kate, Hasegawa, Tetsuo, Kwon, Woojin, Lai, Shih-Ping, Ward-Thompson, Derek, Ching, Tao-Chung, Chen, Zhiwei, Gu, Qilao, Li, Dalei, Li, Hua-Bai et al. 2019. "The JCMT BISTRO Survey: The Magnetic Field in the Starless Core ρ Ophiuchus C." The Astrophysical Journal 877:43. https://doi.org/10.3847/1538-4357/ab0958
ID: 151856
Type: article
Authors: Liu, Junhao; Qiu, Keping; Berry, David; di Francesco, James; Bastien, Pierre; Koch, Patrick M.; Furuya, Ray S.; Kim, Kee-Tae; Coudé, Simon; Lee, Chang Won; Soam, Archana; Eswaraiah, Chakali; Li, Di; Hwang, Jihye; Lyo, A. -Ran; Pattle, Kate; Hasegawa, Tetsuo; Kwon, Woojin; Lai, Shih-Ping; Ward-Thompson, Derek; Ching, Tao-Chung; Chen, Zhiwei; Gu, Qilao; Li, Dalei; Li, Hua-Bai; Liu, Hong-Li; Qian, Lei; Wang, Hongchi; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhang, Ya-Peng; Zhou, Jianjun; Zhu, Lei; André, Philippe; Arzoumanian, Doris; Aso, Yusuke; Byun, Do-Young; Chen, Michael Chun-Yuan; Chen, Huei-Ru Vivien; Chen, Wen Ping; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Dowell, C. Darren; Eyres, Stewart P. S.; Falle, Sam; Fanciullo, Lapo; Fiege, Jason; Franzmann, Erica; Friberg, Per; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Han, Ilseung; Hatchell, Jennifer; Hayashi, Saeko S.; Hoang, Thiem; Holland, Wayne; Houde, Martin; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Johnstone, Doug; Kanamori, Yoshihiro; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kataoka, Akimasa; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Kusune, Takayoshi; Kwon, Jungmi; Lacaille, Kevin M.; Lee, Chin-Fei; Lee, Jeong-Eun; Lee, Hyeseung; Lee, Sang-Sung; Liu, Sheng-Yuan; Liu, Tie; Van Loo, Sven; Mairs, Steve; Matsumura, Masafumi; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Parker, Josh; Parsons, Harriet; Pascale, Enzo; Peretto, Nicolas; Pon, Andy; Pyo, Tae-Soo; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Sadavoy, Sarah; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Zenko, Tetsuya
Abstract: We report 850 μm dust polarization observations of a low-mass (∼12 M ⊙) starless core in the ρ Ophiuchus cloud, Ophiuchus C, made with the POL-2 instrument on the James Clerk Maxwell Telescope (JCMT) as part of the JCMT B-fields In STar-forming Region Observations survey. We detect an ordered magnetic field projected on the plane of the sky in the starless core. The magnetic field across the ∼0.1 pc core shows a predominant northeast–southwest orientation centering between ∼40° and ∼100°, indicating that the field in the core is well aligned with the magnetic field in lower-density regions of the cloud probed by near-infrared observations and also the cloud-scale magnetic field traced by Planck observations. The polarization percentage (P) decreases with increasing total intensity (I), with a power-law index of ‑1.03 ± 0.05. We estimate the plane-of-sky field strength (B pos) using modified Davis–Chandrasekhar–Fermi methods based on structure function (SF), autocorrelation function (ACF), and unsharp masking (UM) analyses. We find that the estimates from the SF, ACF, and UM methods yield strengths of 103 ± 46 μG, 136 ± 69 μG, and 213 ± 115 μG, respectively. Our calculations suggest that the Ophiuchus C core is near magnetically critical or slightly magnetically supercritical (i.e., unstable to collapse). The total magnetic energy calculated from the SF method is comparable to the turbulent energy in Ophiuchus C, while the ACF method and the UM method only set upper limits for the total magnetic energy because of large uncertainties.
Type: article
Authors: Liu, Junhao; Qiu, Keping; Berry, David; di Francesco, James; Bastien, Pierre; Koch, Patrick M.; Furuya, Ray S.; Kim, Kee-Tae; Coudé, Simon; Lee, Chang Won; Soam, Archana; Eswaraiah, Chakali; Li, Di; Hwang, Jihye; Lyo, A. -Ran; Pattle, Kate; Hasegawa, Tetsuo; Kwon, Woojin; Lai, Shih-Ping; Ward-Thompson, Derek; Ching, Tao-Chung; Chen, Zhiwei; Gu, Qilao; Li, Dalei; Li, Hua-Bai; Liu, Hong-Li; Qian, Lei; Wang, Hongchi; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhang, Ya-Peng; Zhou, Jianjun; Zhu, Lei; André, Philippe; Arzoumanian, Doris; Aso, Yusuke; Byun, Do-Young; Chen, Michael Chun-Yuan; Chen, Huei-Ru Vivien; Chen, Wen Ping; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Dowell, C. Darren; Eyres, Stewart P. S.; Falle, Sam; Fanciullo, Lapo; Fiege, Jason; Franzmann, Erica; Friberg, Per; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Han, Ilseung; Hatchell, Jennifer; Hayashi, Saeko S.; Hoang, Thiem; Holland, Wayne; Houde, Martin; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Johnstone, Doug; Kanamori, Yoshihiro; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kataoka, Akimasa; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Kusune, Takayoshi; Kwon, Jungmi; Lacaille, Kevin M.; Lee, Chin-Fei; Lee, Jeong-Eun; Lee, Hyeseung; Lee, Sang-Sung; Liu, Sheng-Yuan; Liu, Tie; Van Loo, Sven; Mairs, Steve; Matsumura, Masafumi; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Parker, Josh; Parsons, Harriet; Pascale, Enzo; Peretto, Nicolas; Pon, Andy; Pyo, Tae-Soo; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Sadavoy, Sarah; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Zenko, Tetsuya
Abstract: We report 850 μm dust polarization observations of a low-mass (∼12 M ⊙) starless core in the ρ Ophiuchus cloud, Ophiuchus C, made with the POL-2 instrument on the James Clerk Maxwell Telescope (JCMT) as part of the JCMT B-fields In STar-forming Region Observations survey. We detect an ordered magnetic field projected on the plane of the sky in the starless core. The magnetic field across the ∼0.1 pc core shows a predominant northeast–southwest orientation centering between ∼40° and ∼100°, indicating that the field in the core is well aligned with the magnetic field in lower-density regions of the cloud probed by near-infrared observations and also the cloud-scale magnetic field traced by Planck observations. The polarization percentage (P) decreases with increasing total intensity (I), with a power-law index of ‑1.03 ± 0.05. We estimate the plane-of-sky field strength (B pos) using modified Davis–Chandrasekhar–Fermi methods based on structure function (SF), autocorrelation function (ACF), and unsharp masking (UM) analyses. We find that the estimates from the SF, ACF, and UM methods yield strengths of 103 ± 46 μG, 136 ± 69 μG, and 213 ± 115 μG, respectively. Our calculations suggest that the Ophiuchus C core is near magnetically critical or slightly magnetically supercritical (i.e., unstable to collapse). The total magnetic energy calculated from the SF method is comparable to the turbulent energy in Ophiuchus C, while the ACF method and the UM method only set upper limits for the total magnetic energy because of large uncertainties.
The 2005-2016 Trends of Formaldehyde Columns Over China Observed by Satellites: Increasing Anthropogenic Emissions of Volatile Organic Compounds and Decreasing Agricultural Fire EmissionsShen, LuJacob, Daniel J.Zhu, LeiZhang, QiangZheng, BoSulprizio, Melissa P.Li, KeDe Smedt, IsabelleGonzález Abad, GonzaloCao, HansenFu, Tzung-MayLiao, HongDOI: info:10.1029/2019GL082172v. 464468–4475
Shen, Lu, Jacob, Daniel J., Zhu, Lei, Zhang, Qiang, Zheng, Bo, Sulprizio, Melissa P., Li, Ke, De Smedt, Isabelle, González Abad, Gonzalo, Cao, Hansen, Fu, Tzung-May, and Liao, Hong. 2019. "The 2005-2016 Trends of Formaldehyde Columns Over China Observed by Satellites: Increasing Anthropogenic Emissions of Volatile Organic Compounds and Decreasing Agricultural Fire Emissions." Geophysical Research Letters 46:4468– 4475. https://doi.org/10.1029/2019GL082172
ID: 155159
Type: article
Authors: Shen, Lu; Jacob, Daniel J.; Zhu, Lei; Zhang, Qiang; Zheng, Bo; Sulprizio, Melissa P.; Li, Ke; De Smedt, Isabelle; González Abad, Gonzalo; Cao, Hansen; Fu, Tzung-May; Liao, Hong
Abstract: We use 2005-2016 observations of formaldehyde (HCHO) columns over China from the OMI, GOME-2, and SCIAMACHY satellite instruments to evaluate long-term trends in emission inventories of volatile organic compounds (VOCs) that affect air quality. The observations show large increases over 2005-2016 in the North China Plain (+1.1 ± 0.5% a-1 relative to 2005) and the Yangtze River Delta region (+1.5 ± 0.4% a-1 relative to 2005), consistent with the trend of anthropogenic VOC emissions in the Multi-resolution Emission Inventory for China (MEIC). Unlike other pollutants, VOC emissions have not been decreasing in recent years. An exception is the Huai River Basin in rural eastern China where the satellite data show rapidly decreasing VOC emissions since the early 2010s that appear to reflect bans on agricultural fires.
Type: article
Authors: Shen, Lu; Jacob, Daniel J.; Zhu, Lei; Zhang, Qiang; Zheng, Bo; Sulprizio, Melissa P.; Li, Ke; De Smedt, Isabelle; González Abad, Gonzalo; Cao, Hansen; Fu, Tzung-May; Liao, Hong
Abstract: We use 2005-2016 observations of formaldehyde (HCHO) columns over China from the OMI, GOME-2, and SCIAMACHY satellite instruments to evaluate long-term trends in emission inventories of volatile organic compounds (VOCs) that affect air quality. The observations show large increases over 2005-2016 in the North China Plain (+1.1 ± 0.5% a-1 relative to 2005) and the Yangtze River Delta region (+1.5 ± 0.4% a-1 relative to 2005), consistent with the trend of anthropogenic VOC emissions in the Multi-resolution Emission Inventory for China (MEIC). Unlike other pollutants, VOC emissions have not been decreasing in recent years. An exception is the Huai River Basin in rural eastern China where the satellite data show rapidly decreasing VOC emissions since the early 2010s that appear to reflect bans on agricultural fires.
JCMT BISTRO Survey: Magnetic Fields within the Hub-filament Structure in IC 5146Wang, Jia-WeiLai, Shih-PingEswaraiah, ChakaliPattle, Katedi Francesco, JamesJohnstone, DougKoch, Patrick M.Liu, TieTamura, MotohideFuruya, Ray S.Onaka, TakashiWard-Thompson, DerekSoam, ArchanaKim, Kee-TaeLee, Chang WonLee, Chin-FeiMairs, SteveArzoumanian, DorisKim, GwanjeongHoang, ThiemHwang, JihyeLiu, Sheng-YuanBerry, DavidBastien, PierreHasegawa, TetsuoKwon, WoojinQiu, KepingAndré, PhilippeAso, YusukeByun, Do-YoungChen, Huei-RuChen, Michael C.Chen, Wen PingChing, Tao-ChungCho, JungyeonChoi, MinhoChrysostomou, AntonioChung, Eun JungCoudé, SimonDoi, YasuoDowell, C. DarrenDrabek-Maunder, EmilyDuan, Hao-YuanEyres, Stewart P. S.Falle, SamFanciullo, LapoFiege, JasonFranzmann, EricaFriberg, PerFriesen, Rachel K.Fuller, GaryGledhill, TimGraves, Sarah F.Greaves, Jane S.Griffin, Matt J.Gu, QilaoHan, IlseungHatchell, JenniferHayashi, Saeko S.Holland, WayneHoude, MartinInoue, TsuyoshiInutsuka, Shu-ichiroIwasaki, KazunariJeong, Il-GyoKanamori, YoshihiroKang, Ji-hyunKang, MijuKang, Sung-juKataoka, AkimasaKawabata, Koji S.Kemper, FranciscaKim, JongsooKim, Kyoung HeeKim, Mi-RyangKim, ShinyoungKirk, Jason M.Kobayashi, Masato I. N.Konyves, VeraKwon, JungmiLacaille, Kevin M.Lee, HyeseungLee, Jeong-EunLee, Sang-SungLee, Yong-HeeLi, DaleiLi, DiLi, Hua-BaiLiu, Hong-LiLiu, JunhaoLyo, A. -RanMatsumura, MasafumiMatthews, Brenda C.Moriarty-Schieven, Gerald H.Nagata, TetsuyaNakamura, FumitakaNakanishi, HiroyukiOhashi, NagayoshiPark, GeumsookParsons, HarrietPascale, EnzoPeretto, NicolasPon, AndyPyo, Tae-SooQian, LeiRao, RamprasadRawlings, Mark G.Retter, BrendanRicher, JohnRigby, AndrewRobitaille, Jean-FrançoisSadavoy, SarahSaito, HiroSavini, GiorgioScaife, Anna M. M.Seta, MasumichiShinnaga, HirokoTang, Ya-WenTomisaka, KohjiTsukamoto, YusukeVan Loo, SvenWang, HongchiWhitworth, Anthony P.Yen, Hsi-WeiYoo, HyunjuYuan, JinghuaYun, Hyeong-SikZenko, TetsuyaZhang, Chuan-PengZhang, GuoyinZhang, Ya-PengZhou, JianjunZhu, LeiDOI: info:10.3847/1538-4357/ab13a2v. 87642
Wang, Jia-Wei, Lai, Shih-Ping, Eswaraiah, Chakali, Pattle, Kate, di Francesco, James, Johnstone, Doug, Koch, Patrick M., Liu, Tie, Tamura, Motohide, Furuya, Ray S., Onaka, Takashi, Ward-Thompson, Derek, Soam, Archana, Kim, Kee-Tae, Lee, Chang Won, Lee, Chin-Fei, Mairs, Steve, Arzoumanian, Doris, Kim, Gwanjeong, Hoang, Thiem, Hwang, Jihye, Liu, Sheng-Yuan, Berry, David, Bastien, Pierre, Hasegawa, Tetsuo et al. 2019. "JCMT BISTRO Survey: Magnetic Fields within the Hub-filament Structure in IC 5146." The Astrophysical Journal 876:42. https://doi.org/10.3847/1538-4357/ab13a2
ID: 151857
Type: article
Authors: Wang, Jia-Wei; Lai, Shih-Ping; Eswaraiah, Chakali; Pattle, Kate; di Francesco, James; Johnstone, Doug; Koch, Patrick M.; Liu, Tie; Tamura, Motohide; Furuya, Ray S.; Onaka, Takashi; Ward-Thompson, Derek; Soam, Archana; Kim, Kee-Tae; Lee, Chang Won; Lee, Chin-Fei; Mairs, Steve; Arzoumanian, Doris; Kim, Gwanjeong; Hoang, Thiem; Hwang, Jihye; Liu, Sheng-Yuan; Berry, David; Bastien, Pierre; Hasegawa, Tetsuo; Kwon, Woojin; Qiu, Keping; André, Philippe; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Michael C.; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Coudé, Simon; Doi, Yasuo; Dowell, C. Darren; Drabek-Maunder, Emily; Duan, Hao-Yuan; Eyres, Stewart P. S.; Falle, Sam; Fanciullo, Lapo; Fiege, Jason; Franzmann, Erica; Friberg, Per; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Gu, Qilao; Han, Ilseung; Hatchell, Jennifer; Hayashi, Saeko S.; Holland, Wayne; Houde, Martin; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kanamori, Yoshihiro; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kataoka, Akimasa; Kawabata, Koji S.; Kemper, Francisca; Kim, Jongsoo; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Konyves, Vera; Kwon, Jungmi; Lacaille, Kevin M.; Lee, Hyeseung; Lee, Jeong-Eun; Lee, Sang-Sung; Lee, Yong-Hee; Li, Dalei; Li, Di; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Lyo, A. -Ran; Matsumura, Masafumi; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Park, Geumsook; Parsons, Harriet; Pascale, Enzo; Peretto, Nicolas; Pon, Andy; Pyo, Tae-Soo; Qian, Lei; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Sadavoy, Sarah; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Van Loo, Sven; Wang, Hongchi; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Yun, Hyeong-Sik; Zenko, Tetsuya; Zhang, Chuan-Peng; Zhang, Guoyin; Zhang, Ya-Peng; Zhou, Jianjun; Zhu, Lei
Abstract: We present the 850 μm polarization observations toward the IC 5146 filamentary cloud taken using the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) and its associated polarimeter (POL-2), mounted on the James Clerk Maxwell Telescope, as part of the B-fields In STar forming Regions Observations. This work is aimed at revealing the magnetic field morphology within a core-scale (≲1.0 pc) hub-filament structure (HFS) located at the end of a parsec-scale filament. To investigate whether the observed polarization traces the magnetic field in the HFS, we analyze the dependence between the observed polarization fraction and total intensity using a Bayesian approach with the polarization fraction described by the Rice likelihood function, which can correctly describe the probability density function of the observed polarization fraction for low signal-to-noise ratio data. We find a power-law dependence between the polarization fraction and total intensity with an index of 0.56 in A V ∼ 20–300 mag regions, suggesting that the dust grains in these dense regions can still be aligned with magnetic fields in the IC 5146 regions. Our polarization maps reveal a curved magnetic field, possibly dragged by the contraction along the parsec-scale filament. We further obtain a magnetic field strength of 0.5 ± 0.2 mG toward the central hub using the Davis–Chandrasekhar–Fermi method, corresponding to a mass-to-flux criticality of ∼1.3 ± 0.4 and an Alfvénic Mach number of <0.6. These results suggest that gravity and magnetic field are currently of comparable importance in the HFS and that turbulence is less important.
Type: article
Authors: Wang, Jia-Wei; Lai, Shih-Ping; Eswaraiah, Chakali; Pattle, Kate; di Francesco, James; Johnstone, Doug; Koch, Patrick M.; Liu, Tie; Tamura, Motohide; Furuya, Ray S.; Onaka, Takashi; Ward-Thompson, Derek; Soam, Archana; Kim, Kee-Tae; Lee, Chang Won; Lee, Chin-Fei; Mairs, Steve; Arzoumanian, Doris; Kim, Gwanjeong; Hoang, Thiem; Hwang, Jihye; Liu, Sheng-Yuan; Berry, David; Bastien, Pierre; Hasegawa, Tetsuo; Kwon, Woojin; Qiu, Keping; André, Philippe; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Michael C.; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Choi, Minho; Chrysostomou, Antonio; Chung, Eun Jung; Coudé, Simon; Doi, Yasuo; Dowell, C. Darren; Drabek-Maunder, Emily; Duan, Hao-Yuan; Eyres, Stewart P. S.; Falle, Sam; Fanciullo, Lapo; Fiege, Jason; Franzmann, Erica; Friberg, Per; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Graves, Sarah F.; Greaves, Jane S.; Griffin, Matt J.; Gu, Qilao; Han, Ilseung; Hatchell, Jennifer; Hayashi, Saeko S.; Holland, Wayne; Houde, Martin; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kanamori, Yoshihiro; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kataoka, Akimasa; Kawabata, Koji S.; Kemper, Francisca; Kim, Jongsoo; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Kirk, Jason M.; Kobayashi, Masato I. N.; Konyves, Vera; Kwon, Jungmi; Lacaille, Kevin M.; Lee, Hyeseung; Lee, Jeong-Eun; Lee, Sang-Sung; Lee, Yong-Hee; Li, Dalei; Li, Di; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Lyo, A. -Ran; Matsumura, Masafumi; Matthews, Brenda C.; Moriarty-Schieven, Gerald H.; Nagata, Tetsuya; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Park, Geumsook; Parsons, Harriet; Pascale, Enzo; Peretto, Nicolas; Pon, Andy; Pyo, Tae-Soo; Qian, Lei; Rao, Ramprasad; Rawlings, Mark G.; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Sadavoy, Sarah; Saito, Hiro; Savini, Giorgio; Scaife, Anna M. M.; Seta, Masumichi; Shinnaga, Hiroko; Tang, Ya-Wen; Tomisaka, Kohji; Tsukamoto, Yusuke; Van Loo, Sven; Wang, Hongchi; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Yun, Hyeong-Sik; Zenko, Tetsuya; Zhang, Chuan-Peng; Zhang, Guoyin; Zhang, Ya-Peng; Zhou, Jianjun; Zhu, Lei
Abstract: We present the 850 μm polarization observations toward the IC 5146 filamentary cloud taken using the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) and its associated polarimeter (POL-2), mounted on the James Clerk Maxwell Telescope, as part of the B-fields In STar forming Regions Observations. This work is aimed at revealing the magnetic field morphology within a core-scale (≲1.0 pc) hub-filament structure (HFS) located at the end of a parsec-scale filament. To investigate whether the observed polarization traces the magnetic field in the HFS, we analyze the dependence between the observed polarization fraction and total intensity using a Bayesian approach with the polarization fraction described by the Rice likelihood function, which can correctly describe the probability density function of the observed polarization fraction for low signal-to-noise ratio data. We find a power-law dependence between the polarization fraction and total intensity with an index of 0.56 in A V ∼ 20–300 mag regions, suggesting that the dust grains in these dense regions can still be aligned with magnetic fields in the IC 5146 regions. Our polarization maps reveal a curved magnetic field, possibly dragged by the contraction along the parsec-scale filament. We further obtain a magnetic field strength of 0.5 ± 0.2 mG toward the central hub using the Davis–Chandrasekhar–Fermi method, corresponding to a mass-to-flux criticality of ∼1.3 ± 0.4 and an Alfvénic Mach number of <0.6. These results suggest that gravity and magnetic field are currently of comparable importance in the HFS and that turbulence is less important.
A First Look at BISTRO Observations of the rho Oph-A coreKwon, JungmiDoi, YasuoTamura, MotohideMatsumura, MasafumiPattle, KateBerry, DavidSadavoy, SarahMatthews, Brenda C.Ward-Thompson, DerekHasegawa, TetsuoFuruya, Ray S.Pon, Andydi Francesco, JamesArzoumanian, DorisHayashi, Saeko S.Kawabata, Koji S.Onaka, TakashiChoi, MinhoKang, MijuHoang, ThiemLee, Chang WonLee, Sang-SungLiu, Hong-LiLiu, TieInutsuka, Shu-ichiroEswaraiah, ChakaliBastien, PierreKwon, WoojinLai, Shih-PingQiu, KepingCoudé, SimonFranzmann, EricaFriberg, PerGraves, Sarah F.Greaves, Jane S.Houde, MartinJohnstone, DougKirk, Jason M.Koch, Patrick M.Li, DiParsons, HarrietRao, RamprasadRawlings, Mark G.Shinnaga, HirokoVan Loo, SvenAso, YusukeByun, Do-YoungChen, Huei-RuChen, Mike C. -YChen, Wen PingChing, Tao-ChungCho, JungyeonChrysostomou, AntonioChung, Eun JungDrabek-Maunder, EmilyEyres, Stewart P. S.Fiege, JasonFriesen, Rachel K.Fuller, GaryGledhill, TimGriffin, Matt J.Gu, QilaoHatchell, JenniferHolland, WayneInoue, TsuyoshiIwasaki, KazunariJeong, Il-GyoKang, Ji-hyunKang, Sung-juKemper, FranciscaKim, GwanjeongKim, JongsooKim, Kee-TaeKim, Kyoung HeeKim, Mi-RyangKim, ShinyoungLacaille, Kevin M.Lee, Jeong-EunLi, DaleiLi, Hua-BaiLiu, JunhaoLiu, Sheng-YuanLyo, A. -RanMairs, SteveMoriarty-Schieven, Gerald H.Nakamura, FumitakaNakanishi, HiroyukiOhashi, NagayoshiPeretto, NicolasPyo, Tae-SooQian, LeiRetter, BrendanRicher, JohnRigby, AndrewRobitaille, Jean-FranoisSavini, GiorgioScaife, Anna M. M.Soam, ArchanaTang, Ya-WenTomisaka, KohjiWang, HongchiWang, Jia-WeiWhitworth, Anthony P.Yen, Hsi-WeiYoo, HyunjuYuan, JinghuaZhang, Chuan-PengZhang, GuoyinZhou, JianjunZhu, LeiAndré, PhilippeDowell, C. DarrenFalle, SamTsukamoto, YusukeNakagawa, TakaoKanamori, YoshihiroKataoka, AkimasaKobayashi, Masato I. N.Nagata, TetsuyaSaito, HiroSeta, MasumichiZenko, TetsuyaDOI: info:10.3847/1538-4357/aabd82v. 8594
Kwon, Jungmi, Doi, Yasuo, Tamura, Motohide, Matsumura, Masafumi, Pattle, Kate, Berry, David, Sadavoy, Sarah, Matthews, Brenda C., Ward-Thompson, Derek, Hasegawa, Tetsuo, Furuya, Ray S., Pon, Andy, di Francesco, James, Arzoumanian, Doris, Hayashi, Saeko S., Kawabata, Koji S., Onaka, Takashi, Choi, Minho, Kang, Miju, Hoang, Thiem, Lee, Chang Won, Lee, Sang-Sung, Liu, Hong-Li, Liu, Tie, Inutsuka, Shu-ichiro et al. 2018. "A First Look at BISTRO Observations of the rho Oph-A core." The Astrophysical Journal 859:4. https://doi.org/10.3847/1538-4357/aabd82
ID: 147424
Type: article
Authors: Kwon, Jungmi; Doi, Yasuo; Tamura, Motohide; Matsumura, Masafumi; Pattle, Kate; Berry, David; Sadavoy, Sarah; Matthews, Brenda C.; Ward-Thompson, Derek; Hasegawa, Tetsuo; Furuya, Ray S.; Pon, Andy; di Francesco, James; Arzoumanian, Doris; Hayashi, Saeko S.; Kawabata, Koji S.; Onaka, Takashi; Choi, Minho; Kang, Miju; Hoang, Thiem; Lee, Chang Won; Lee, Sang-Sung; Liu, Hong-Li; Liu, Tie; Inutsuka, Shu-ichiro; Eswaraiah, Chakali; Bastien, Pierre; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Coudé, Simon; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Li, Di; Parsons, Harriet; Rao, Ramprasad; Rawlings, Mark G.; Shinnaga, Hiroko; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hatchell, Jennifer; Holland, Wayne; Inoue, Tsuyoshi; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Sung-ju; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Li, Dalei; Li, Hua-Bai; Liu, Junhao; Liu, Sheng-Yuan; Lyo, A. -Ran; Mairs, Steve; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-Franois; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke; Nakagawa, Takao; Kanamori, Yoshihiro; Kataoka, Akimasa; Kobayashi, Masato I. N.; Nagata, Tetsuya; Saito, Hiro; Seta, Masumichi; Zenko, Tetsuya
Abstract: We present 850 mum imaging polarimetry data of the rho Oph-A core taken with the Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part of our ongoing survey project, {\boldsymbol{B}}-fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify the orientation of the magnetic field projected on the plane of the sky at a resolution of 0.01 pc. We identify 10 subregions with distinct polarization fractions and angles in the 0.2 pc rho Oph-A core; some of them can be part of a coherent magnetic field structure in the rho Oph region. The results are consistent with previous observations of the brightest regions of rho Oph-A, where the degrees of polarization are at a level of a few percent, but our data reveal for the first time the magnetic field structures in the fainter regions surrounding the core where the degree of polarization is much higher (>5%). A comparison with previous near-infrared polarimetric data shows that there are several magnetic field components that are consistent at near-infrared and submillimeter wavelengths. Using the Davis--Chandrasekhar--Fermi method, we also derive magnetic field strengths in several subcore regions, which range from approximately 0.2 to 5 mG. We also find a correlation between the magnetic field orientations projected on the sky and the core centroid velocity components.
Type: article
Authors: Kwon, Jungmi; Doi, Yasuo; Tamura, Motohide; Matsumura, Masafumi; Pattle, Kate; Berry, David; Sadavoy, Sarah; Matthews, Brenda C.; Ward-Thompson, Derek; Hasegawa, Tetsuo; Furuya, Ray S.; Pon, Andy; di Francesco, James; Arzoumanian, Doris; Hayashi, Saeko S.; Kawabata, Koji S.; Onaka, Takashi; Choi, Minho; Kang, Miju; Hoang, Thiem; Lee, Chang Won; Lee, Sang-Sung; Liu, Hong-Li; Liu, Tie; Inutsuka, Shu-ichiro; Eswaraiah, Chakali; Bastien, Pierre; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Coudé, Simon; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Li, Di; Parsons, Harriet; Rao, Ramprasad; Rawlings, Mark G.; Shinnaga, Hiroko; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hatchell, Jennifer; Holland, Wayne; Inoue, Tsuyoshi; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Sung-ju; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Li, Dalei; Li, Hua-Bai; Liu, Junhao; Liu, Sheng-Yuan; Lyo, A. -Ran; Mairs, Steve; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-Franois; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke; Nakagawa, Takao; Kanamori, Yoshihiro; Kataoka, Akimasa; Kobayashi, Masato I. N.; Nagata, Tetsuya; Saito, Hiro; Seta, Masumichi; Zenko, Tetsuya
Abstract: We present 850 mum imaging polarimetry data of the rho Oph-A core taken with the Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part of our ongoing survey project, {\boldsymbol{B}}-fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify the orientation of the magnetic field projected on the plane of the sky at a resolution of 0.01 pc. We identify 10 subregions with distinct polarization fractions and angles in the 0.2 pc rho Oph-A core; some of them can be part of a coherent magnetic field structure in the rho Oph region. The results are consistent with previous observations of the brightest regions of rho Oph-A, where the degrees of polarization are at a level of a few percent, but our data reveal for the first time the magnetic field structures in the fainter regions surrounding the core where the degree of polarization is much higher (>5%). A comparison with previous near-infrared polarimetric data shows that there are several magnetic field components that are consistent at near-infrared and submillimeter wavelengths. Using the Davis--Chandrasekhar--Fermi method, we also derive magnetic field strengths in several subcore regions, which range from approximately 0.2 to 5 mG. We also find a correlation between the magnetic field orientations projected on the sky and the core centroid velocity components.
The TOP-SCOPE Survey of Planck Galactic Cold Clumps: Survey Overview and Results of an Exemplar Source, PGCC G26.53+0.17Liu, TieKim, Kee-TaeJuvela, MikaWang, KeTatematsu, Ken'ichidi Francesco, JamesLiu, Sheng-YuanWu, YuefangThompson, MarkFuller, GaryEden, DavidLi, DiRistorcelli, I.Kang, Sung-juLin, YuxinJohnstone, D.He, J. H.Koch, P. M.Sanhueza, PatricioQin, Sheng-LiZhang, QizhouHirano, N.Goldsmith, Paul F.Evans, Neal J., IIWhite, Glenn J.Choi, MinhoLee, Chang WonToth, L. V.Mairs, SteveYi, H. -WTang, MengyaoSoam, ArchanaPeretto, N.Samal, Manash R.Fich, MichelParsons, HarrietYuan, JinghuaZhang, Chuan-PengMalinen, JohannaBendo, George J.Rivera-Ingraham, A.Liu, Hong-LiWouterloot, JanLi, Pak ShingQian, LeiRawlings, JonathanRawlings, Mark G.Feng, SiyiAikawa, YuriAkhter, S.Alina, DanaBell, GrahamBernard, J. -PBlain, AndrewBőgner, RebekaBronfman, L.Byun, D. -YChapman, ScottChen, Huei-RuChen, M.Chen, Wen-PingChen, X.Chen, XuepengChrysostomou, A.Cosentino, GiulianaCunningham, M. R.Demyk, K.Drabek-Maunder, EmilyDoi, YasuoEswaraiah, C.Falgarone, EdithFehér, O.Fraser, HelenFriberg, PerGaray, G.Ge, J. X.Gear, W. K.Greaves, JaneGuan, X.Harvey-Smith, LisaHasegawa, TetsuoHatchell, J.He, YuxinHenkel, C.Hirota, T.Holland, W.Hughes, A.Jarken, E.Ji, Tae-GeunJimenez-Serra, IzaskunKang, MijuKawabata, Koji S.Kim, GwanjeongKim, JunghaKim, JongsooKim, ShinyoungKoo, B. -CKwon, WoojinKuan, Yi-JehngLacaille, K. M.Lai, Shih-PingLee, C. F.Lee, J. -ELee, Y. -ULi, DaleiLi, Hua-BaiLo, N.Lopez, John A. P.Lu, XingLyo, A. -RanMardones, D.Marston, A.McGehee, P.Meng, F.Montier, L.Montillaud, JulienMoore, T.Morata, O.Moriarty-Schieven, Gerald H.Ohashi, S.Pak, SoojongPark, GeumsookPaladini, R.Pattle, Kate M.Pech, GerardoPelkonen, V. -MQiu, K.Ren, Zhi-YuanRicher, JohnSaito, M.Sakai, TakeshiShang, H.Shinnaga, HirokoStamatellos, DimitrisTang, Y. -WTraficante, AlessioVastel, CharlotteViti, S.Walsh, AndrewWang, BingruWang, HongchiWang, JunzhiWard-Thompson, D.Whitworth, AnthonyXu, YeYang, J.Yang, Yao-LunYuan, LixiaZavagno, A.Zhang, GuoyinZhang, H. -WZhou, ChenlinZhou, JianjunZhu, LeiZuo, PeiZhang, ChaoDOI: info:10.3847/1538-4365/aaa3ddv. 23428
Liu, Tie, Kim, Kee-Tae, Juvela, Mika, Wang, Ke, Tatematsu, Ken'ichi, di Francesco, James, Liu, Sheng-Yuan, Wu, Yuefang, Thompson, Mark, Fuller, Gary, Eden, David, Li, Di, Ristorcelli, I., Kang, Sung-ju, Lin, Yuxin, Johnstone, D., He, J. H., Koch, P. M., Sanhueza, Patricio, Qin, Sheng-Li, Zhang, Qizhou, Hirano, N., Goldsmith, Paul F., Evans, Neal J., II, White, Glenn J. et al. 2018. "The TOP-SCOPE Survey of Planck Galactic Cold Clumps: Survey Overview and Results of an Exemplar Source, PGCC G26.53+0.17." The Astrophysical Journal Supplement Series 234:28. https://doi.org/10.3847/1538-4365/aaa3dd
ID: 145792
Type: article
Authors: Liu, Tie; Kim, Kee-Tae; Juvela, Mika; Wang, Ke; Tatematsu, Ken'ichi; di Francesco, James; Liu, Sheng-Yuan; Wu, Yuefang; Thompson, Mark; Fuller, Gary; Eden, David; Li, Di; Ristorcelli, I.; Kang, Sung-ju; Lin, Yuxin; Johnstone, D.; He, J. H.; Koch, P. M.; Sanhueza, Patricio; Qin, Sheng-Li; Zhang, Qizhou; Hirano, N.; Goldsmith, Paul F.; Evans, Neal J., II; White, Glenn J.; Choi, Minho; Lee, Chang Won; Toth, L. V.; Mairs, Steve; Yi, H. -W; Tang, Mengyao; Soam, Archana; Peretto, N.; Samal, Manash R.; Fich, Michel; Parsons, Harriet; Yuan, Jinghua; Zhang, Chuan-Peng; Malinen, Johanna; Bendo, George J.; Rivera-Ingraham, A.; Liu, Hong-Li; Wouterloot, Jan; Li, Pak Shing; Qian, Lei; Rawlings, Jonathan; Rawlings, Mark G.; Feng, Siyi; Aikawa, Yuri; Akhter, S.; Alina, Dana; Bell, Graham; Bernard, J. -P; Blain, Andrew; Bőgner, Rebeka; Bronfman, L.; Byun, D. -Y; Chapman, Scott; Chen, Huei-Ru; Chen, M.; Chen, Wen-Ping; Chen, X.; Chen, Xuepeng; Chrysostomou, A.; Cosentino, Giuliana; Cunningham, M. R.; Demyk, K.; Drabek-Maunder, Emily; Doi, Yasuo; Eswaraiah, C.; Falgarone, Edith; Fehér, O.; Fraser, Helen; Friberg, Per; Garay, G.; Ge, J. X.; Gear, W. K.; Greaves, Jane; Guan, X.; Harvey-Smith, Lisa; Hasegawa, Tetsuo; Hatchell, J.; He, Yuxin; Henkel, C.; Hirota, T.; Holland, W.; Hughes, A.; Jarken, E.; Ji, Tae-Geun; Jimenez-Serra, Izaskun; Kang, Miju; Kawabata, Koji S.; Kim, Gwanjeong; Kim, Jungha; Kim, Jongsoo; Kim, Shinyoung; Koo, B. -C; Kwon, Woojin; Kuan, Yi-Jehng; Lacaille, K. M.; Lai, Shih-Ping; Lee, C. F.; Lee, J. -E; Lee, Y. -U; Li, Dalei; Li, Hua-Bai; Lo, N.; Lopez, John A. P.; Lu, Xing; Lyo, A. -Ran; Mardones, D.; Marston, A.; McGehee, P.; Meng, F.; Montier, L.; Montillaud, Julien; Moore, T.; Morata, O.; Moriarty-Schieven, Gerald H.; Ohashi, S.; Pak, Soojong; Park, Geumsook; Paladini, R.; Pattle, Kate M.; Pech, Gerardo; Pelkonen, V. -M; Qiu, K.; Ren, Zhi-Yuan; Richer, John; Saito, M.; Sakai, Takeshi; Shang, H.; Shinnaga, Hiroko; Stamatellos, Dimitris; Tang, Y. -W; Traficante, Alessio; Vastel, Charlotte; Viti, S.; Walsh, Andrew; Wang, Bingru; Wang, Hongchi; Wang, Junzhi; Ward-Thompson, D.; Whitworth, Anthony; Xu, Ye; Yang, J.; Yang, Yao-Lun; Yuan, Lixia; Zavagno, A.; Zhang, Guoyin; Zhang, H. -W; Zhou, Chenlin; Zhou, Jianjun; Zhu, Lei; Zuo, Pei; Zhang, Chao
Abstract: The low dust temperatures (⊙, ∼12 pc, and ∼500 M ⊙ pc‑1, respectively. Ten massive clumps, including eight starless ones, are found along the filament. The most massive clump as a whole may still be in global collapse, while its denser part seems to be undergoing expansion owing to outflow feedback. The fragmentation in the G26 filament from cloud scale to clump scale is in agreement with gravitational fragmentation of an isothermal, nonmagnetized, and turbulent supported cylinder. A bimodal behavior in dust emissivity spectral index (β) distribution is found in G26, suggesting grain growth along the filament. The G26 filament may be formed owing to large-scale compression flows evidenced by the temperature and velocity gradients across its natal cloud.
Type: article
Authors: Liu, Tie; Kim, Kee-Tae; Juvela, Mika; Wang, Ke; Tatematsu, Ken'ichi; di Francesco, James; Liu, Sheng-Yuan; Wu, Yuefang; Thompson, Mark; Fuller, Gary; Eden, David; Li, Di; Ristorcelli, I.; Kang, Sung-ju; Lin, Yuxin; Johnstone, D.; He, J. H.; Koch, P. M.; Sanhueza, Patricio; Qin, Sheng-Li; Zhang, Qizhou; Hirano, N.; Goldsmith, Paul F.; Evans, Neal J., II; White, Glenn J.; Choi, Minho; Lee, Chang Won; Toth, L. V.; Mairs, Steve; Yi, H. -W; Tang, Mengyao; Soam, Archana; Peretto, N.; Samal, Manash R.; Fich, Michel; Parsons, Harriet; Yuan, Jinghua; Zhang, Chuan-Peng; Malinen, Johanna; Bendo, George J.; Rivera-Ingraham, A.; Liu, Hong-Li; Wouterloot, Jan; Li, Pak Shing; Qian, Lei; Rawlings, Jonathan; Rawlings, Mark G.; Feng, Siyi; Aikawa, Yuri; Akhter, S.; Alina, Dana; Bell, Graham; Bernard, J. -P; Blain, Andrew; Bőgner, Rebeka; Bronfman, L.; Byun, D. -Y; Chapman, Scott; Chen, Huei-Ru; Chen, M.; Chen, Wen-Ping; Chen, X.; Chen, Xuepeng; Chrysostomou, A.; Cosentino, Giuliana; Cunningham, M. R.; Demyk, K.; Drabek-Maunder, Emily; Doi, Yasuo; Eswaraiah, C.; Falgarone, Edith; Fehér, O.; Fraser, Helen; Friberg, Per; Garay, G.; Ge, J. X.; Gear, W. K.; Greaves, Jane; Guan, X.; Harvey-Smith, Lisa; Hasegawa, Tetsuo; Hatchell, J.; He, Yuxin; Henkel, C.; Hirota, T.; Holland, W.; Hughes, A.; Jarken, E.; Ji, Tae-Geun; Jimenez-Serra, Izaskun; Kang, Miju; Kawabata, Koji S.; Kim, Gwanjeong; Kim, Jungha; Kim, Jongsoo; Kim, Shinyoung; Koo, B. -C; Kwon, Woojin; Kuan, Yi-Jehng; Lacaille, K. M.; Lai, Shih-Ping; Lee, C. F.; Lee, J. -E; Lee, Y. -U; Li, Dalei; Li, Hua-Bai; Lo, N.; Lopez, John A. P.; Lu, Xing; Lyo, A. -Ran; Mardones, D.; Marston, A.; McGehee, P.; Meng, F.; Montier, L.; Montillaud, Julien; Moore, T.; Morata, O.; Moriarty-Schieven, Gerald H.; Ohashi, S.; Pak, Soojong; Park, Geumsook; Paladini, R.; Pattle, Kate M.; Pech, Gerardo; Pelkonen, V. -M; Qiu, K.; Ren, Zhi-Yuan; Richer, John; Saito, M.; Sakai, Takeshi; Shang, H.; Shinnaga, Hiroko; Stamatellos, Dimitris; Tang, Y. -W; Traficante, Alessio; Vastel, Charlotte; Viti, S.; Walsh, Andrew; Wang, Bingru; Wang, Hongchi; Wang, Junzhi; Ward-Thompson, D.; Whitworth, Anthony; Xu, Ye; Yang, J.; Yang, Yao-Lun; Yuan, Lixia; Zavagno, A.; Zhang, Guoyin; Zhang, H. -W; Zhou, Chenlin; Zhou, Jianjun; Zhu, Lei; Zuo, Pei; Zhang, Chao
Abstract: The low dust temperatures (⊙, ∼12 pc, and ∼500 M ⊙ pc‑1, respectively. Ten massive clumps, including eight starless ones, are found along the filament. The most massive clump as a whole may still be in global collapse, while its denser part seems to be undergoing expansion owing to outflow feedback. The fragmentation in the G26 filament from cloud scale to clump scale is in agreement with gravitational fragmentation of an isothermal, nonmagnetized, and turbulent supported cylinder. A bimodal behavior in dust emissivity spectral index (β) distribution is found in G26, suggesting grain growth along the filament. The G26 filament may be formed owing to large-scale compression flows evidenced by the temperature and velocity gradients across its natal cloud.
Magnetic Fields toward Ophiuchus-B Derived from SCUBA-2 Polarization MeasurementsSoam, ArchanaPattle, KateWard-Thompson, DerekLee, Chang WonSadavoy, SarahKoch, Patrick M.Kim, GwanjeongKwon, JungmiKwon, WoojinArzoumanian, DorisBerry, DavidHoang, ThiemTamura, MotohideLee, Sang-SungLiu, TieKim, Kee-TaeJohnstone, DougNakamura, FumitakaLyo, A. -RanOnaka, TakashiKim, JongsooFuruya, Ray S.Hasegawa, TetsuoLai, Shih-PingBastien, PierreChung, Eun JungKim, ShinyoungParsons, HarrietRawlings, Mark G.Mairs, SteveGraves, Sarah F.Robitaille, Jean-FranoisLiu, Hong-LiWhitworth, Anthony P.Eswaraiah, ChakaliRao, RamprasadYoo, HyunjuHoude, MartinKang, Ji-hyunDoi, YasuoChoi, MinhoKang, MijuCoudé, SimonLi, Hua-BaiMatsumura, MasafumiMatthews, Brenda C.Pon, Andydi Francesco, JamesHayashi, Saeko S.Kawabata, Koji S.Inutsuka, Shu-ichiroQiu, KepingFranzmann, EricaFriberg, PerGreaves, Jane S.Kirk, Jason M.Li, DiShinnaga, HirokoVan Loo, SvenAso, YusukeByun, Do-YoungChen, Huei-RuChen, Mike C. -YChen, Wen PingChing, Tao-ChungCho, JungyeonChrysostomou, AntonioDrabek-Maunder, EmilyEyres, Stewart P. S.Fiege, JasonFriesen, Rachel K.Fuller, GaryGledhill, TimGriffin, Matt J.Gu, QilaoHatchell, JenniferHolland, WayneInoue, TsuyoshiIwasaki, KazunariJeong, Il-GyoKang, Sung-juKemper, FranciscaKim, Kyoung HeeKim, Mi-RyangLacaille, Kevin M.Lee, Jeong-EunLi, DaleiLiu, JunhaoLiu, Sheng-YuanMoriarty-Schieven, Gerald H.Nakanishi, HiroyukiOhashi, NagayoshiPeretto, NicolasPyo, Tae-SooQian, LeiRetter, BrendanRicher, JohnRigby, AndrewSavini, GiorgioScaife, Anna M. M.Tang, Ya-WenTomisaka, KohjiWang, HongchiWang, Jia-WeiYen, Hsi-WeiYuan, JinghuaZhang, Chuan-PengZhang, GuoyinZhou, JianjunZhu, LeiAndré, PhilippeDowell, C. DarrenFalle, SamTsukamoto, YusukeKanamori, YoshihiroKataoka, AkimasaKobayashi, Masato I. N.Nagata, TetsuyaSaito, HiroSeta, MasumichiHwang, JihyeHan, IlseungLee, HyeseungZenko, TetsuyaDOI: info:10.3847/1538-4357/aac4a6v. 86165
Soam, Archana, Pattle, Kate, Ward-Thompson, Derek, Lee, Chang Won, Sadavoy, Sarah, Koch, Patrick M., Kim, Gwanjeong, Kwon, Jungmi, Kwon, Woojin, Arzoumanian, Doris, Berry, David, Hoang, Thiem, Tamura, Motohide, Lee, Sang-Sung, Liu, Tie, Kim, Kee-Tae, Johnstone, Doug, Nakamura, Fumitaka, Lyo, A. -Ran, Onaka, Takashi, Kim, Jongsoo, Furuya, Ray S., Hasegawa, Tetsuo, Lai, Shih-Ping, Bastien, Pierre et al. 2018. "Magnetic Fields toward Ophiuchus-B Derived from SCUBA-2 Polarization Measurements." The Astrophysical Journal 861:65. https://doi.org/10.3847/1538-4357/aac4a6
ID: 147915
Type: article
Authors: Soam, Archana; Pattle, Kate; Ward-Thompson, Derek; Lee, Chang Won; Sadavoy, Sarah; Koch, Patrick M.; Kim, Gwanjeong; Kwon, Jungmi; Kwon, Woojin; Arzoumanian, Doris; Berry, David; Hoang, Thiem; Tamura, Motohide; Lee, Sang-Sung; Liu, Tie; Kim, Kee-Tae; Johnstone, Doug; Nakamura, Fumitaka; Lyo, A. -Ran; Onaka, Takashi; Kim, Jongsoo; Furuya, Ray S.; Hasegawa, Tetsuo; Lai, Shih-Ping; Bastien, Pierre; Chung, Eun Jung; Kim, Shinyoung; Parsons, Harriet; Rawlings, Mark G.; Mairs, Steve; Graves, Sarah F.; Robitaille, Jean-Franois; Liu, Hong-Li; Whitworth, Anthony P.; Eswaraiah, Chakali; Rao, Ramprasad; Yoo, Hyunju; Houde, Martin; Kang, Ji-hyun; Doi, Yasuo; Choi, Minho; Kang, Miju; Coudé, Simon; Li, Hua-Bai; Matsumura, Masafumi; Matthews, Brenda C.; Pon, Andy; di Francesco, James; Hayashi, Saeko S.; Kawabata, Koji S.; Inutsuka, Shu-ichiro; Qiu, Keping; Franzmann, Erica; Friberg, Per; Greaves, Jane S.; Kirk, Jason M.; Li, Di; Shinnaga, Hiroko; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hatchell, Jennifer; Holland, Wayne; Inoue, Tsuyoshi; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Sung-ju; Kemper, Francisca; Kim, Kyoung Hee; Kim, Mi-Ryang; Lacaille, Kevin M.; Lee, Jeong-Eun; Li, Dalei; Liu, Junhao; Liu, Sheng-Yuan; Moriarty-Schieven, Gerald H.; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Savini, Giorgio; Scaife, Anna M. M.; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Yen, Hsi-Wei; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke; Kanamori, Yoshihiro; Kataoka, Akimasa; Kobayashi, Masato I. N.; Nagata, Tetsuya; Saito, Hiro; Seta, Masumichi; Hwang, Jihye; Han, Ilseung; Lee, Hyeseung; Zenko, Tetsuya
Abstract: We present the results of dust emission polarization measurements of Ophiuchus-B (Oph-B) carried out using the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera with its associated polarimeter (POL-2) on the James Clerk Maxwell Telescope in Hawaii. This work is part of the B-fields in Star-forming Region Observations survey initiated to understand the role of magnetic fields in star formation for nearby star-forming molecular clouds. We present a first look at the geometry and strength of magnetic fields in Oph-B. The field geometry is traced over ~0.2 pc, with clear detection of both of the sub-clumps of Oph-B. The field pattern appears significantly disordered in sub-clump Oph-B1. The field geometry in Oph-B2 is more ordered, with a tendency to be along the major axis of the clump, parallel to the filamentary structure within which it lies. The degree of polarization decreases systematically toward the dense core material in the two sub-clumps. The field lines in the lower density material along the periphery are smoothly joined to the large-scale magnetic fields probed by NIR polarization observations. We estimated a magnetic field strength of 630 ± 410 muG in the Oph-B2 sub-clump using a Davis--Chandrasekhar--Fermi analysis. With this magnetic field strength, we find a mass-to-flux ratio lambda = 1.6 ± 1.1, which suggests that the Oph-B2 clump is slightly magnetically supercritical.
Type: article
Authors: Soam, Archana; Pattle, Kate; Ward-Thompson, Derek; Lee, Chang Won; Sadavoy, Sarah; Koch, Patrick M.; Kim, Gwanjeong; Kwon, Jungmi; Kwon, Woojin; Arzoumanian, Doris; Berry, David; Hoang, Thiem; Tamura, Motohide; Lee, Sang-Sung; Liu, Tie; Kim, Kee-Tae; Johnstone, Doug; Nakamura, Fumitaka; Lyo, A. -Ran; Onaka, Takashi; Kim, Jongsoo; Furuya, Ray S.; Hasegawa, Tetsuo; Lai, Shih-Ping; Bastien, Pierre; Chung, Eun Jung; Kim, Shinyoung; Parsons, Harriet; Rawlings, Mark G.; Mairs, Steve; Graves, Sarah F.; Robitaille, Jean-Franois; Liu, Hong-Li; Whitworth, Anthony P.; Eswaraiah, Chakali; Rao, Ramprasad; Yoo, Hyunju; Houde, Martin; Kang, Ji-hyun; Doi, Yasuo; Choi, Minho; Kang, Miju; Coudé, Simon; Li, Hua-Bai; Matsumura, Masafumi; Matthews, Brenda C.; Pon, Andy; di Francesco, James; Hayashi, Saeko S.; Kawabata, Koji S.; Inutsuka, Shu-ichiro; Qiu, Keping; Franzmann, Erica; Friberg, Per; Greaves, Jane S.; Kirk, Jason M.; Li, Di; Shinnaga, Hiroko; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hatchell, Jennifer; Holland, Wayne; Inoue, Tsuyoshi; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Sung-ju; Kemper, Francisca; Kim, Kyoung Hee; Kim, Mi-Ryang; Lacaille, Kevin M.; Lee, Jeong-Eun; Li, Dalei; Liu, Junhao; Liu, Sheng-Yuan; Moriarty-Schieven, Gerald H.; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Savini, Giorgio; Scaife, Anna M. M.; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Yen, Hsi-Wei; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke; Kanamori, Yoshihiro; Kataoka, Akimasa; Kobayashi, Masato I. N.; Nagata, Tetsuya; Saito, Hiro; Seta, Masumichi; Hwang, Jihye; Han, Ilseung; Lee, Hyeseung; Zenko, Tetsuya
Abstract: We present the results of dust emission polarization measurements of Ophiuchus-B (Oph-B) carried out using the Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera with its associated polarimeter (POL-2) on the James Clerk Maxwell Telescope in Hawaii. This work is part of the B-fields in Star-forming Region Observations survey initiated to understand the role of magnetic fields in star formation for nearby star-forming molecular clouds. We present a first look at the geometry and strength of magnetic fields in Oph-B. The field geometry is traced over ~0.2 pc, with clear detection of both of the sub-clumps of Oph-B. The field pattern appears significantly disordered in sub-clump Oph-B1. The field geometry in Oph-B2 is more ordered, with a tendency to be along the major axis of the clump, parallel to the filamentary structure within which it lies. The degree of polarization decreases systematically toward the dense core material in the two sub-clumps. The field lines in the lower density material along the periphery are smoothly joined to the large-scale magnetic fields probed by NIR polarization observations. We estimated a magnetic field strength of 630 ± 410 muG in the Oph-B2 sub-clump using a Davis--Chandrasekhar--Fermi analysis. With this magnetic field strength, we find a mass-to-flux ratio lambda = 1.6 ± 1.1, which suggests that the Oph-B2 clump is slightly magnetically supercritical.
Glyoxal yield from isoprene oxidation and relation to formaldehyde: chemical mechanism, constraints from SENEX aircraft observations, and interpretation of OMI satellite dataChan Miller, ChristopherJacob, Daniel J.Marais, Eloise A.Yu, KarenTravis, Katherine R.Kim, Patrick S.Fisher, Jenny A.Zhu, LeiWolfe, Glenn M.Hanisco, Thomas F.Keutsch, Frank N.Kaiser, JenniferMin, Kyung-EunBrown, Steven S.Washenfelder, Rebecca A.González Abad, GonzaloChance, KellyDOI: info:10.5194/acp-17-8725-2017v. 178725–8738
Chan Miller, Christopher, Jacob, Daniel J., Marais, Eloise A., Yu, Karen, Travis, Katherine R., Kim, Patrick S., Fisher, Jenny A., Zhu, Lei, Wolfe, Glenn M., Hanisco, Thomas F., Keutsch, Frank N., Kaiser, Jennifer, Min, Kyung-Eun, Brown, Steven S., Washenfelder, Rebecca A., González Abad, Gonzalo, and Chance, Kelly. 2017. "Glyoxal yield from isoprene oxidation and relation to formaldehyde: chemical mechanism, constraints from SENEX aircraft observations, and interpretation of OMI satellite data." Atmospheric Chemistry & Physics 17:8725– 8738. https://doi.org/10.5194/acp-17-8725-2017
ID: 143830
Type: article
Authors: Chan Miller, Christopher; Jacob, Daniel J.; Marais, Eloise A.; Yu, Karen; Travis, Katherine R.; Kim, Patrick S.; Fisher, Jenny A.; Zhu, Lei; Wolfe, Glenn M.; Hanisco, Thomas F.; Keutsch, Frank N.; Kaiser, Jennifer; Min, Kyung-Eun; Brown, Steven S.; Washenfelder, Rebecca A.; González Abad, Gonzalo; Chance, Kelly
Abstract: Glyoxal (CHOCHO) is produced in the atmosphere by the oxidation of volatile organic compounds (VOCs). Like formaldehyde (HCHO), another VOC oxidation product, it is measurable from space by solar backscatter. Isoprene emitted by vegetation is the dominant source of CHOCHO and HCHO in most of the world. We use aircraft observations of CHOCHO and HCHO from the SENEX campaign over the southeast US in summer 2013 to better understand the CHOCHO time-dependent yield from isoprene oxidation, its dependence on nitrogen oxides (NOx ≡ NO + NO2), the behavior of the CHOCHO-HCHO relationship, the quality of OMI CHOCHO satellite observations, and the implications for using CHOCHO observations from space as constraints on isoprene emissions. We simulate the SENEX and OMI observations with the Goddard Earth Observing System chemical transport model (GEOS-Chem) featuring a new chemical mechanism for CHOCHO formation from isoprene. The mechanism includes prompt CHOCHO formation under low-NOx conditions following the isomerization of the isoprene peroxy radical (ISOPO2). The SENEX observations provide support for this prompt CHOCHO formation pathway, and are generally consistent with the GEOS-Chem mechanism. Boundary layer CHOCHO and HCHO are strongly correlated in the observations and the model, with some departure under low-NOx conditions due to prompt CHOCHO formation. SENEX vertical profiles indicate a free-tropospheric CHOCHO background that is absent from the model. The OMI CHOCHO data provide some support for this free-tropospheric background and show southeast US enhancements consistent with the isoprene source but a factor of 2 too low. Part of this OMI bias is due to excessive surface reflectivities assumed in the retrieval. The OMI CHOCHO and HCHO seasonal data over the southeast US are tightly correlated and provide redundant proxies of isoprene emissions. Higher temporal resolution in future geostationary satellite observations may enable detection of the prompt CHOCHO production under low-NOx conditions apparent in the SENEX data.
Type: article
Authors: Chan Miller, Christopher; Jacob, Daniel J.; Marais, Eloise A.; Yu, Karen; Travis, Katherine R.; Kim, Patrick S.; Fisher, Jenny A.; Zhu, Lei; Wolfe, Glenn M.; Hanisco, Thomas F.; Keutsch, Frank N.; Kaiser, Jennifer; Min, Kyung-Eun; Brown, Steven S.; Washenfelder, Rebecca A.; González Abad, Gonzalo; Chance, Kelly
Abstract: Glyoxal (CHOCHO) is produced in the atmosphere by the oxidation of volatile organic compounds (VOCs). Like formaldehyde (HCHO), another VOC oxidation product, it is measurable from space by solar backscatter. Isoprene emitted by vegetation is the dominant source of CHOCHO and HCHO in most of the world. We use aircraft observations of CHOCHO and HCHO from the SENEX campaign over the southeast US in summer 2013 to better understand the CHOCHO time-dependent yield from isoprene oxidation, its dependence on nitrogen oxides (NOx ≡ NO + NO2), the behavior of the CHOCHO-HCHO relationship, the quality of OMI CHOCHO satellite observations, and the implications for using CHOCHO observations from space as constraints on isoprene emissions. We simulate the SENEX and OMI observations with the Goddard Earth Observing System chemical transport model (GEOS-Chem) featuring a new chemical mechanism for CHOCHO formation from isoprene. The mechanism includes prompt CHOCHO formation under low-NOx conditions following the isomerization of the isoprene peroxy radical (ISOPO2). The SENEX observations provide support for this prompt CHOCHO formation pathway, and are generally consistent with the GEOS-Chem mechanism. Boundary layer CHOCHO and HCHO are strongly correlated in the observations and the model, with some departure under low-NOx conditions due to prompt CHOCHO formation. SENEX vertical profiles indicate a free-tropospheric CHOCHO background that is absent from the model. The OMI CHOCHO data provide some support for this free-tropospheric background and show southeast US enhancements consistent with the isoprene source but a factor of 2 too low. Part of this OMI bias is due to excessive surface reflectivities assumed in the retrieval. The OMI CHOCHO and HCHO seasonal data over the southeast US are tightly correlated and provide redundant proxies of isoprene emissions. Higher temporal resolution in future geostationary satellite observations may enable detection of the prompt CHOCHO production under low-NOx conditions apparent in the SENEX data.
First Results from BISTRO: A SCUBA-2 Polarimeter Survey of the Gould BeltWard-Thompson, DerekPattle, KateBastien, PierreFuruya, Ray S.Kwon, WoojinLai, Shih-PingQiu, KepingBerry, DavidChoi, MinhoCoudé, Simondi Francesco, JamesHoang, ThiemFranzmann, EricaFriberg, PerGraves, Sarah F.Greaves, Jane S.Houde, MartinJohnstone, DougKirk, Jason M.Koch, Patrick M.Kwon, JungmiLee, Chang WonLi, DiMatthews, Brenda C.Mottram, Joseph C.Parsons, HarrietPon, AndyRao, RamprasadRawlings, MarkShinnaga, HirokoSadavoy, SarahVan Loo, SvenAso, YusukeByun, Do-YoungEswaraiah, ChakaliChen, Huei-RuChen, Mike C. -YChen, Wen PingChing, Tao-ChungCho, JungyeonChrysostomou, AntonioChung, Eun JungDoi, YasuoDrabek-Maunder, EmilyEyres, Stewart P. S.Fiege, JasonFriesen, Rachel K.Fuller, GaryGledhill, TimGriffin, Matt J.Gu, QilaoHasegawa, TetsuoHatchell, JenniferHayashi, Saeko S.Holland, WayneInoue, TsuyoshiInutsuka, Shu-ichiroIwasaki, KazunariJeong, Il-GyoKang, Ji-hyunKang, MijuKang, Sung-juKawabata, Koji S.Kemper, FranciscaKim, GwanjeongKim, JongsooKim, Kee-TaeKim, Kyoung HeeKim, Mi-RyangKim, ShinyoungLacaille, Kevin M.Lee, Jeong-EunLee, Sang-SungLi, DaleiLi, Hua-BaiLiu, Hong-LiLiu, JunhaoLiu, Sheng-YuanLiu, TieLyo, A. -RanMairs, SteveMatsumura, MasafumiMoriarty-Schieven, Gerald H.Nakamura, FumitakaNakanishi, HiroyukiOhashi, NagayoshiOnaka, TakashiPeretto, NicolasPyo, Tae-SooQian, LeiRetter, BrendanRicher, JohnRigby, AndrewRobitaille, Jean-FrançoisSavini, GiorgioScaife, Anna M. M.Soam, ArchanaTamura, MotohideTang, Ya-WenTomisaka, KohjiWang, HongchiWang, Jia-WeiWhitworth, Anthony P.Yen, Hsi-WeiYoo, HyunjuYuan, JinghuaZhang, Chuan-PengZhang, GuoyinZhou, JianjunZhu, LeiAndré, PhilippeDowell, C. DarrenFalle, SamTsukamoto, YusukeDOI: info:10.3847/1538-4357/aa70a0v. 84266
Ward-Thompson, Derek, Pattle, Kate, Bastien, Pierre, Furuya, Ray S., Kwon, Woojin, Lai, Shih-Ping, Qiu, Keping, Berry, David, Choi, Minho, Coudé, Simon, di Francesco, James, Hoang, Thiem, Franzmann, Erica, Friberg, Per, Graves, Sarah F., Greaves, Jane S., Houde, Martin, Johnstone, Doug, Kirk, Jason M., Koch, Patrick M., Kwon, Jungmi, Lee, Chang Won, Li, Di, Matthews, Brenda C., Mottram, Joseph C. et al. 2017. "First Results from BISTRO: A SCUBA-2 Polarimeter Survey of the Gould Belt." The Astrophysical Journal 842:66. https://doi.org/10.3847/1538-4357/aa70a0
ID: 143364
Type: article
Authors: Ward-Thompson, Derek; Pattle, Kate; Bastien, Pierre; Furuya, Ray S.; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Berry, David; Choi, Minho; Coudé, Simon; di Francesco, James; Hoang, Thiem; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Kwon, Jungmi; Lee, Chang Won; Li, Di; Matthews, Brenda C.; Mottram, Joseph C.; Parsons, Harriet; Pon, Andy; Rao, Ramprasad; Rawlings, Mark; Shinnaga, Hiroko; Sadavoy, Sarah; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Eswaraiah, Chakali; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hasegawa, Tetsuo; Hatchell, Jennifer; Hayashi, Saeko S.; Holland, Wayne; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Lee, Sang-Sung; Li, Dalei; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Liu, Sheng-Yuan; Liu, Tie; Lyo, A. -Ran; Mairs, Steve; Matsumura, Masafumi; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke
Abstract: We present the first results from the B-fields In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope in Hawaii. We discuss the survey's aims and objectives. We describe the rationale behind the survey, and the questions that the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability and consistency with previous data. We present a first-look analysis of the first results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous "integral filament" in the densest regions of that filament. Furthermore, we see an "hourglass" magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density northeastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments.
Type: article
Authors: Ward-Thompson, Derek; Pattle, Kate; Bastien, Pierre; Furuya, Ray S.; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Berry, David; Choi, Minho; Coudé, Simon; di Francesco, James; Hoang, Thiem; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Kwon, Jungmi; Lee, Chang Won; Li, Di; Matthews, Brenda C.; Mottram, Joseph C.; Parsons, Harriet; Pon, Andy; Rao, Ramprasad; Rawlings, Mark; Shinnaga, Hiroko; Sadavoy, Sarah; Van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Eswaraiah, Chakali; Chen, Huei-Ru; Chen, Mike C. -Y; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hasegawa, Tetsuo; Hatchell, Jennifer; Hayashi, Saeko S.; Holland, Wayne; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Lee, Sang-Sung; Li, Dalei; Li, Hua-Bai; Liu, Hong-Li; Liu, Junhao; Liu, Sheng-Yuan; Liu, Tie; Lyo, A. -Ran; Mairs, Steve; Matsumura, Masafumi; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke
Abstract: We present the first results from the B-fields In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope in Hawaii. We discuss the survey's aims and objectives. We describe the rationale behind the survey, and the questions that the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability and consistency with previous data. We present a first-look analysis of the first results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous "integral filament" in the densest regions of that filament. Furthermore, we see an "hourglass" magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density northeastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments.
Observing atmospheric formaldehyde (HCHO) from space: validation and intercomparison of six retrievals from four satellites (OMI, GOME2A, GOME2B, OMPS) with SEAC4RS aircraft observations over the southeast USZhu, LeiJacob, Daniel J.Kim, Patrick S.Fisher, Jenny A.Yu, KarenTravis, Katherine R.Mickley, Loretta J.Yantosca, Robert M.Sulprizio, Melissa P.De Smedt, IsabelleGonzález Abad, GonzaloChance, Kelly V.Li, CanFerrare, RichardFried, AlanHair, Johnathan W.Hanisco, Thomas F.Richter, DirkScarino, Amy JoWalega, JamesWeibring, PetterWolfe, Glenn M.DOI: info:10.5194/acp-16-13477-2016v. 1613477–13490
Zhu, Lei, Jacob, Daniel J., Kim, Patrick S., Fisher, Jenny A., Yu, Karen, Travis, Katherine R., Mickley, Loretta J., Yantosca, Robert M., Sulprizio, Melissa P., De Smedt, Isabelle, González Abad, Gonzalo, Chance, Kelly V., Li, Can, Ferrare, Richard, Fried, Alan, Hair, Johnathan W., Hanisco, Thomas F., Richter, Dirk, Scarino, Amy Jo, Walega, James, Weibring, Petter, and Wolfe, Glenn M. 2016. "Observing atmospheric formaldehyde (HCHO) from space: validation and intercomparison of six retrievals from four satellites (OMI, GOME2A, GOME2B, OMPS) with SEAC4RS aircraft observations over the southeast US." Atmospheric Chemistry & Physics 16:13477– 13490. https://doi.org/10.5194/acp-16-13477-2016
ID: 141926
Type: article
Authors: Zhu, Lei; Jacob, Daniel J.; Kim, Patrick S.; Fisher, Jenny A.; Yu, Karen; Travis, Katherine R.; Mickley, Loretta J.; Yantosca, Robert M.; Sulprizio, Melissa P.; De Smedt, Isabelle; González Abad, Gonzalo; Chance, Kelly V.; Li, Can; Ferrare, Richard; Fried, Alan; Hair, Johnathan W.; Hanisco, Thomas F.; Richter, Dirk; Scarino, Amy Jo; Walega, James; Weibring, Petter; Wolfe, Glenn M.
Abstract: Formaldehyde (HCHO) column data from satellites are widely used as a proxy for emissions of volatile organic compounds (VOCs), but validation of the data has been extremely limited. Here we use highly accurate HCHO aircraft observations from the NASA SEAC4RS (Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys) campaign over the southeast US in August-September 2013 to validate and intercompare six retrievals of HCHO columns from four different satellite instruments (OMI, GOME2A, GOME2B and OMPS; for clarification of these and other abbreviations used in the paper, please refer to Appendix A) and three different research groups. The GEOS-Chem chemical transport model is used as a common intercomparison platform. All retrievals feature a HCHO maximum over Arkansas and Louisiana, consistent with the aircraft observations and reflecting high emissions of biogenic isoprene. The retrievals are also interconsistent in their spatial variability over the southeast US (r = 0.4-0.8 on a 0.5° × 0.5° grid) and in their day-to-day variability (r = 0.5-0.8). However, all retrievals are biased low in the mean by 20-51 %, which would lead to corresponding bias in estimates of isoprene emissions from the satellite data. The smallest bias is for OMI-BIRA, which has high corrected slant columns relative to the other retrievals and low scattering weights in its air mass factor (AMF) calculation. OMI-BIRA has systematic error in its assumed vertical HCHO shape profiles for the AMF calculation, and correcting this would eliminate its bias relative to the SEAC4RS data. Our results support the use of satellite HCHO data as a quantitative proxy for isoprene emission after correction of the low mean bias. There is no evident pattern in the bias, suggesting that a uniform correction factor may be applied to the data until better understanding is achieved.
Type: article
Authors: Zhu, Lei; Jacob, Daniel J.; Kim, Patrick S.; Fisher, Jenny A.; Yu, Karen; Travis, Katherine R.; Mickley, Loretta J.; Yantosca, Robert M.; Sulprizio, Melissa P.; De Smedt, Isabelle; González Abad, Gonzalo; Chance, Kelly V.; Li, Can; Ferrare, Richard; Fried, Alan; Hair, Johnathan W.; Hanisco, Thomas F.; Richter, Dirk; Scarino, Amy Jo; Walega, James; Weibring, Petter; Wolfe, Glenn M.
Abstract: Formaldehyde (HCHO) column data from satellites are widely used as a proxy for emissions of volatile organic compounds (VOCs), but validation of the data has been extremely limited. Here we use highly accurate HCHO aircraft observations from the NASA SEAC4RS (Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys) campaign over the southeast US in August-September 2013 to validate and intercompare six retrievals of HCHO columns from four different satellite instruments (OMI, GOME2A, GOME2B and OMPS; for clarification of these and other abbreviations used in the paper, please refer to Appendix A) and three different research groups. The GEOS-Chem chemical transport model is used as a common intercomparison platform. All retrievals feature a HCHO maximum over Arkansas and Louisiana, consistent with the aircraft observations and reflecting high emissions of biogenic isoprene. The retrievals are also interconsistent in their spatial variability over the southeast US (r = 0.4-0.8 on a 0.5° × 0.5° grid) and in their day-to-day variability (r = 0.5-0.8). However, all retrievals are biased low in the mean by 20-51 %, which would lead to corresponding bias in estimates of isoprene emissions from the satellite data. The smallest bias is for OMI-BIRA, which has high corrected slant columns relative to the other retrievals and low scattering weights in its air mass factor (AMF) calculation. OMI-BIRA has systematic error in its assumed vertical HCHO shape profiles for the AMF calculation, and correcting this would eliminate its bias relative to the SEAC4RS data. Our results support the use of satellite HCHO data as a quantitative proxy for isoprene emission after correction of the low mean bias. There is no evident pattern in the bias, suggesting that a uniform correction factor may be applied to the data until better understanding is achieved.
Anthropogenic emissions of highly reactive volatile organic compounds in eastern Texas inferred from oversampling of satellite (OMI) measurements of HCHO columnsZhu, LeiJacob, Daniel J.Mickley, Loretta J.Marais, Eloïse A.Cohan, Daniel S.Yoshida, YasukoDuncan, Bryan N.González Abad, GonzaloChance, Kelly V.DOI: info:10.1088/1748-9326/9/11/114004v. 9114004
Zhu, Lei, Jacob, Daniel J., Mickley, Loretta J., Marais, Eloïse A., Cohan, Daniel S., Yoshida, Yasuko, Duncan, Bryan N., González Abad, Gonzalo, and Chance, Kelly V. 2014. "Anthropogenic emissions of highly reactive volatile organic compounds in eastern Texas inferred from oversampling of satellite (OMI) measurements of HCHO columns." Environmental Research Letters 9:114004. https://doi.org/10.1088/1748-9326/9/11/114004
ID: 133169
Type: article
Authors: Zhu, Lei; Jacob, Daniel J.; Mickley, Loretta J.; Marais, Eloïse A.; Cohan, Daniel S.; Yoshida, Yasuko; Duncan, Bryan N.; González Abad, Gonzalo; Chance, Kelly V.
Abstract: Satellite observations of formaldehyde (HCHO) columns provide top-down constraints on emissions of highly reactive volatile organic compounds (HRVOCs). This approach has been used previously in the US to estimate isoprene emissions from vegetation, but application to anthropogenic emissions has been stymied by lack of a discernable HCHO signal. Here we show that temporal oversampling of HCHO data from the Ozone Monitoring Instrument (OMI) for 2005-2008 enables detection of urban and industrial plumes in eastern Texas including Houston, Port Arthur, and Dallas/Fort Worth. By spatially integrating the HCHO enhancement in the Houston plume observed by OMI we estimate an anthropogenic HCHO source of 250 ± 140 kmol h-1. This implies that anthropogenic HRVOC emissions in Houston are 4.8 ± 2.7 times higher than reported by the US Environmental Protection Agency inventory, and is consistent with field studies identifying large ethene and propene emissions from petrochemical industrial sources.
Type: article
Authors: Zhu, Lei; Jacob, Daniel J.; Mickley, Loretta J.; Marais, Eloïse A.; Cohan, Daniel S.; Yoshida, Yasuko; Duncan, Bryan N.; González Abad, Gonzalo; Chance, Kelly V.
Abstract: Satellite observations of formaldehyde (HCHO) columns provide top-down constraints on emissions of highly reactive volatile organic compounds (HRVOCs). This approach has been used previously in the US to estimate isoprene emissions from vegetation, but application to anthropogenic emissions has been stymied by lack of a discernable HCHO signal. Here we show that temporal oversampling of HCHO data from the Ozone Monitoring Instrument (OMI) for 2005-2008 enables detection of urban and industrial plumes in eastern Texas including Houston, Port Arthur, and Dallas/Fort Worth. By spatially integrating the HCHO enhancement in the Houston plume observed by OMI we estimate an anthropogenic HCHO source of 250 ± 140 kmol h-1. This implies that anthropogenic HRVOC emissions in Houston are 4.8 ± 2.7 times higher than reported by the US Environmental Protection Agency inventory, and is consistent with field studies identifying large ethene and propene emissions from petrochemical industrial sources.
Subarcsecond Observations of NGC 7538 IRS 1: Continuum Distribution and Dynamics of Molecular GasZhu, LeiZhao, Jun-HuiWright, M. C. H.Sandell, GöranShi, HuiWu, Yue-FangBrogan, CrystalCorder, StuarttDOI: info:10.1088/0004-637X/779/1/51v. 77951
Zhu, Lei, Zhao, Jun-Hui, Wright, M. C. H., Sandell, Göran, Shi, Hui, Wu, Yue-Fang, Brogan, Crystal, and Corder, Stuartt. 2013. "Subarcsecond Observations of NGC 7538 IRS 1: Continuum Distribution and Dynamics of Molecular Gas." The Astrophysical Journal 779:51. https://doi.org/10.1088/0004-637X/779/1/51
ID: 118379
Type: article
Authors: Zhu, Lei; Zhao, Jun-Hui; Wright, M. C. H.; Sandell, Göran; Shi, Hui; Wu, Yue-Fang; Brogan, Crystal; Corder, Stuartt
Abstract: We report new results based on the analysis of the Submillimeter Array (SMA) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of NGC 7538 IRS 1 at 1.3 and 3.4 mm with subarcsecond resolutions. With angular resolutions ~0.''7, the SMA and CARMA observations show that the continuum emission at 1.3 and 3.4 mm from the hyper-compact H II region IRS 1 is dominated by a compact source with a tail-like extended structure to the southwest of IRS 1. With a CARMA B-array image at 1.3 mm convolved to 0.''1, we resolve the hyper-compact H II region into two components: an unresolved hyper-compact core, and a north-south extension with linear sizes of 3CN(12-11) as well as 13CO(2-1) surrounding IRS 1, showing a velocity gradient along the southwest-northeast direction. The spectral line profiles in 13CO(2-1), CO(2-1), and HCN(1-0) observed toward IRS 1 show broad redshifted absorption, providing evidence for gas infall with rates in the range of 3-10 × 10–3 M ? yr–1 inferred from our observations.
Type: article
Authors: Zhu, Lei; Zhao, Jun-Hui; Wright, M. C. H.; Sandell, Göran; Shi, Hui; Wu, Yue-Fang; Brogan, Crystal; Corder, Stuartt
Abstract: We report new results based on the analysis of the Submillimeter Array (SMA) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of NGC 7538 IRS 1 at 1.3 and 3.4 mm with subarcsecond resolutions. With angular resolutions ~0.''7, the SMA and CARMA observations show that the continuum emission at 1.3 and 3.4 mm from the hyper-compact H II region IRS 1 is dominated by a compact source with a tail-like extended structure to the southwest of IRS 1. With a CARMA B-array image at 1.3 mm convolved to 0.''1, we resolve the hyper-compact H II region into two components: an unresolved hyper-compact core, and a north-south extension with linear sizes of 3CN(12-11) as well as 13CO(2-1) surrounding IRS 1, showing a velocity gradient along the southwest-northeast direction. The spectral line profiles in 13CO(2-1), CO(2-1), and HCN(1-0) observed toward IRS 1 show broad redshifted absorption, providing evidence for gas infall with rates in the range of 3-10 × 10–3 M ? yr–1 inferred from our observations.
Observations of a High-mass Protostar in NGC 7538 SWright, MelvynZhao, Jun-HuiSandell, GöranCorder, StuarttGoss, W. M.Zhu, LeiDOI: info:10.1088/0004-637X/746/2/187v. 746No. 2
Wright, Melvyn, Zhao, Jun-Hui, Sandell, Göran, Corder, Stuartt, Goss, W. M., and Zhu, Lei. 2012. "Observations of a High-mass Protostar in NGC 7538 S." The Astrophysical Journal 746 (2):https://doi.org/10.1088/0004-637X/746/2/187
ID: 110288
Type: article
Authors: Wright, Melvyn; Zhao, Jun-Hui; Sandell, Göran; Corder, Stuartt; Goss, W. M.; Zhu, Lei
Abstract: We present high angular resolution continuum observations of the high-mass protostar NGC 7538 S with BIMA and CARMA at 3 and 1.4 mm, Very Large Array (VLA) observations at 1.3, 2, 3.5, and 6 cm, and archive Infrared Array Camera (IRAC) observations from the Spitzer Space Observatory, which detect the star at 4.5, 5.8, and 8 ?m. The star looks rather unremarkable in the mid-IR. The excellent positional agreement of the IRAC source with the VLA free-free emission, the OH, CH3OH, H2O masers, and the dust continuum confirms that this is the most luminous object in the NGC 7538 S core. The continuum emission at millimeter wavelengths is dominated by dust emission from the dense cold cloud core surrounding the protostar. Including all array configurations, the emission is dominated by an elliptical source with a size of ~8'' × 3''. If we filter out the extended emission we find three compact millimeter sources inside the elliptical core. The strongest one, SA, coincides with the VLA/IRAC source and resolves into a double source at 1.4 mm, where we have subarcsecond resolution. The measured spectral index, ?, between 3 and 1.4 mm is ~2.3, and steeper at longer wavelengths, suggesting a low dust emissivity or that the dust is optically thick. We argue that the dust in these accretion disks is optically thick and estimate a mass of an accretion disk or infalling envelope surrounding SA to be ~60 M ?.
Type: article
Authors: Wright, Melvyn; Zhao, Jun-Hui; Sandell, Göran; Corder, Stuartt; Goss, W. M.; Zhu, Lei
Abstract: We present high angular resolution continuum observations of the high-mass protostar NGC 7538 S with BIMA and CARMA at 3 and 1.4 mm, Very Large Array (VLA) observations at 1.3, 2, 3.5, and 6 cm, and archive Infrared Array Camera (IRAC) observations from the Spitzer Space Observatory, which detect the star at 4.5, 5.8, and 8 ?m. The star looks rather unremarkable in the mid-IR. The excellent positional agreement of the IRAC source with the VLA free-free emission, the OH, CH3OH, H2O masers, and the dust continuum confirms that this is the most luminous object in the NGC 7538 S core. The continuum emission at millimeter wavelengths is dominated by dust emission from the dense cold cloud core surrounding the protostar. Including all array configurations, the emission is dominated by an elliptical source with a size of ~8'' × 3''. If we filter out the extended emission we find three compact millimeter sources inside the elliptical core. The strongest one, SA, coincides with the VLA/IRAC source and resolves into a double source at 1.4 mm, where we have subarcsecond resolution. The measured spectral index, ?, between 3 and 1.4 mm is ~2.3, and steeper at longer wavelengths, suggesting a low dust emissivity or that the dust is optically thick. We argue that the dust in these accretion disks is optically thick and estimate a mass of an accretion disk or infalling envelope surrounding SA to be ~60 M ?.
Outflow, Infall, and Protostars in the Star-forming Core W3-SEZhu, LeiZhao, Jun-HuiWright, M. C. H.DOI: info:10.1088/0004-637X/740/2/114v. 740114
Zhu, Lei, Zhao, Jun-Hui, and Wright, M. C. H. 2011. "Outflow, Infall, and Protostars in the Star-forming Core W3-SE." The Astrophysical Journal 740:114. https://doi.org/10.1088/0004-637X/740/2/114
ID: 108042
Type: article
Authors: Zhu, Lei; Zhao, Jun-Hui; Wright, M. C. H.
Abstract: We report new results on outflow and infall in the star-forming cores W3-SE SMA-1 and SMA-2 based on analysis of ~2farcs5 resolution observations of the molecular lines HCN(3-2), HCO+(3-2), N2H+(3-2), and CH3OH(52, 3-41, 3) with the Submillimeter Array (SMA). A high-velocity bipolar outflow originating from the protostellar core SMA-1 was observed in the HCN(3-2) line, with a projected outflow axis
Type: article
Authors: Zhu, Lei; Zhao, Jun-Hui; Wright, M. C. H.
Abstract: We report new results on outflow and infall in the star-forming cores W3-SE SMA-1 and SMA-2 based on analysis of ~2farcs5 resolution observations of the molecular lines HCN(3-2), HCO+(3-2), N2H+(3-2), and CH3OH(52, 3-41, 3) with the Submillimeter Array (SMA). A high-velocity bipolar outflow originating from the protostellar core SMA-1 was observed in the HCN(3-2) line, with a projected outflow axis
Dust and HCO+ Gas in the Star-Forming Core W3-SEZhu, LeiWright, M. C. H.Zhao, Jun-HuiWu, Yuefangv. 712674–684
Zhu, Lei, Wright, M. C. H., Zhao, Jun-Hui, and Wu, Yuefang. 2010. "Dust and HCO+ Gas in the Star-Forming Core W3-SE." The Astrophysical Journal 712:674– 684.