Publication Search Results

Search Results

Showing 1-20 of about 44 results.
The TW Hya Rosetta Stone Project. III. Resolving the Gaseous Thermal Profile of the DiskCalahan, Jenny K.Bergin, EdwinZhang, KeTeague, RichardCleeves, IlsedoreBergner, JenniferBlake, Geoffrey A.Cazzoletti, PaoloGuzmán, VivianaHogerheijde, Michiel R.Huang, JaneKama, MihkelLoomis, RyanÖberg, KarinQi, Charlievan Dishoeck, Ewine F.Terwisscha van Scheltinga, JeroenWalsh, CatherineWilner, DavidDOI: info:10.3847/1538-4357/abd255v. 9088
Calahan, Jenny K., Bergin, Edwin, Zhang, Ke, Teague, Richard, Cleeves, Ilsedore, Bergner, Jennifer, Blake, Geoffrey A., Cazzoletti, Paolo, Guzmán, Viviana, Hogerheijde, Michiel R., Huang, Jane, Kama, Mihkel, Loomis, Ryan, Öberg, Karin, Qi, Charlie, van Dishoeck, Ewine F., Terwisscha van Scheltinga, Jeroen, Walsh, Catherine, and Wilner, David. 2021. "The TW Hya Rosetta Stone Project. III. Resolving the Gaseous Thermal Profile of the Disk." The Astrophysical Journal 908:8. https://doi.org/10.3847/1538-4357/abd255
ID: 159280
Type: article
Authors: Calahan, Jenny K.; Bergin, Edwin; Zhang, Ke; Teague, Richard; Cleeves, Ilsedore; Bergner, Jennifer; Blake, Geoffrey A.; Cazzoletti, Paolo; Guzmán, Viviana; Hogerheijde, Michiel R.; Huang, Jane; Kama, Mihkel; Loomis, Ryan; Öberg, Karin; Qi, Charlie; van Dishoeck, Ewine F.; Terwisscha van Scheltinga, Jeroen; Walsh, Catherine; Wilner, David
Abstract: The thermal structure of protoplanetary disks is a fundamental characteristic of the system that has wide-reaching effects on disk evolution and planet formation. In this study, we constrain the 2D thermal structure of the protoplanetary disk TW Hya structure utilizing images of seven CO lines. This includes new ALMA observations of 12CO J = 2-1 and C18O J = 2-1 as well as archival ALMA observations of 12CO J = 3-2, 13CO J = 3-2 and 6-5, and C18O J = 3-2 and 6-5. Additionally, we reproduce a Herschel observation of the HD J = 1-0 line flux and the spectral energy distribution and utilize a recent quantification of CO radial depletion in TW Hya. These observations were modeled using the thermochemical code RAC2D, and our best-fit model reproduces all spatially resolved CO surface brightness profiles. The resulting thermal profile finds a disk mass of 0.025 M and a thin upper layer of gas depleted of small dust with a thickness of ∼1.2% of the corresponding radius. Using our final thermal structure, we find that CO alone is not a viable mass tracer, as its abundance is degenerate with the total H2 surface density. Different mass models can readily match the spatially resolved CO line profiles with disparate abundance assumptions. Mass determination requires additional knowledge, and, in this work, HD provides the additional constraint to derive the gas mass and support the inference of CO depletion in the TW Hya disk. Our final thermal structure confirms the use of HD as a powerful probe of protoplanetary disk mass. Additionally, the method laid out in this paper is an employable strategy for extraction of disk temperatures and masses in the future.
A Search for Companions via Direct Imaging in the DSHARP Planet-forming DisksJorquera, SebastianPérez, Laura M.Chauvin, GaëlBenisty, MyriamZhu, ZhaohuanIsella, AndreaHuang, JaneRicci, LucaAndrews, Sean M.Zhang, ShangjiaCarpenter, John M.Kurtovic, Nicolás T.Birnstiel, TilmanDOI: info:10.3847/1538-3881/abd40dv. 161146
Jorquera, Sebastian, Pérez, Laura M., Chauvin, Gaël, Benisty, Myriam, Zhu, Zhaohuan, Isella, Andrea, Huang, Jane, Ricci, Luca, Andrews, Sean M., Zhang, Shangjia, Carpenter, John M., Kurtovic, Nicolás T., and Birnstiel, Tilman. 2021. "A Search for Companions via Direct Imaging in the DSHARP Planet-forming Disks." The Astronomical Journal 161:146. https://doi.org/10.3847/1538-3881/abd40d
ID: 159329
Type: article
Authors: Jorquera, Sebastian; Pérez, Laura M.; Chauvin, Gaël; Benisty, Myriam; Zhu, Zhaohuan; Isella, Andrea; Huang, Jane; Ricci, Luca; Andrews, Sean M.; Zhang, Shangjia; Carpenter, John M.; Kurtovic, Nicolás T.; Birnstiel, Tilman
Abstract: The "Disk Substructures at High Angular Resolution Project" (DSHARP) has revealed an abundance and ubiquity of rings and gaps over a large sample of young planet-forming disks, which are hypothesized to be induced by the presence of forming planets. In this context, we present the first attempt to directly image these young companions for 10 of the DSHARP disks, by using the NaCo/VLT high-contrast observations in L' band instrument and angular differential imaging techniques. We report the detection of a point-like source candidate at 1"1 (174.9 au) for RU Lup and at 0"42 (55 au) for Elias 24. In the case of RU Lup, the proper motion of the candidate is consistent with a stationary background contaminant, based on the astrometry derived from our observations and available archival data. For Elias 24 the point-like source candidate is located in one of the disk gaps at 55 au. Assuming that it is a planetary companion, our analysis suggests a mass ranging from 0.5MJ up to 5MJ, depending on the presence of a circumplanetary disk and its contribution to the luminosity of the system. However, no clear confirmation is obtained at this stage, and follow-up observations are mandatory to verify that the proposed source is physical, comoving with the stellar host, and associated with a young massive planet sculpting the gap observed at 55 au. For all the remaining systems, the lack of detections suggests the presence of planetary companions with masses lower than 5MJ, based on our derived mass detection limits. This is consistent with predictions of both hydrodynamical simulations and kinematical signatures on the disk and allows us to set upper limits on the presence of massive planets in these young disks.
Dynamical Masses and Stellar Evolutionary Model Predictions of M StarsPegues, JamilaCzekala, IanAndrews, Sean M.Öberg, Karin I.Herczeg, Gregory J.Bergner, Jennifer B.Ilsedore Cleeves, L.Guzmán, Viviana V.Huang, JaneLong, FengTeague, RichardWilner, David J.DOI: info:10.3847/1538-4357/abd4ebv. 90842
Pegues, Jamila, Czekala, Ian, Andrews, Sean M., Öberg, Karin I., Herczeg, Gregory J., Bergner, Jennifer B., Ilsedore Cleeves, L., Guzmán, Viviana V., Huang, Jane, Long, Feng, Teague, Richard, and Wilner, David J. 2021. "Dynamical Masses and Stellar Evolutionary Model Predictions of M Stars." The Astrophysical Journal 908:42. https://doi.org/10.3847/1538-4357/abd4eb
ID: 159623
Type: article
Authors: Pegues, Jamila; Czekala, Ian; Andrews, Sean M.; Öberg, Karin I.; Herczeg, Gregory J.; Bergner, Jennifer B.; Ilsedore Cleeves, L.; Guzmán, Viviana V.; Huang, Jane; Long, Feng; Teague, Richard; Wilner, David J.
Abstract: In this era of Gaia and ALMA, dynamical stellar mass measurements, derived from spatially and spectrally resolved observations of the Keplerian rotation of circumstellar disks, provide benchmarks that are independent of observations of stellar characteristics and their uncertainties. These benchmarks can then be used to validate and improve stellar evolutionary models, the latter of which can lead to both imprecise and inaccurate mass predictions for pre-main-sequence, low-mass (≤0.5 M) stars. We present the dynamical stellar masses derived from disks around three M stars (FP Tau, J0432+1827, and J1100-7619) using ALMA observations of 12CO (J = 2-1) and 13CO (J = 2-1) emission. These are the first dynamical stellar mass measurements for J0432+1827 and J1100-7619 (0.192 ± 0.005 M and 0.461 ± 0.057 M, respectively) and the most precise measurement for FP Tau (0.395 ± 0.012 M). Fiducial stellar evolutionary model tracks, which do not include any treatment of magnetic activity, agree with the dynamical stellar mass measurement of J0432+1827 but underpredict the mass by ∼60% for FP Tau and by ∼80% for J1100-7619. Possible explanations for the underpredictions include inaccurate assumptions of stellar effective temperature, undetected binarity for J1100-7619, and that fiducial stellar evolutionary models are not complex enough to represent these stars. In the former case, the stellar effective temperatures would need to be increased by amounts ranging from ∼40 to ∼340 K to reconcile the fiducial stellar evolutionary model predictions with the dynamically measured masses. In the latter case, we show that the dynamical masses can be reproduced using results from stellar evolutionary models with starspots, which incorporate fractional starspot coverage to represent the manifestation of magnetic activity. Folding in low-mass M stars from the literature and assuming that the stellar effective temperatures are imprecise but accurate, we find tentative evidence of a relationship between fractional starspot coverage and observed effective temperature for these young, cool stars.
Measured Lightcurves and Rotational Periods of 3122 Florence, 3830 Trelleborg, and (131077) 2000 YH105Abrams, Natasha S.Bieryla, AllysonGomez, SebastianHuang, JaneLewis, John ArbanGarrison, Lehman H.Carmichael, Theronv. 473–4
Abrams, Natasha S., Bieryla, Allyson, Gomez, Sebastian, Huang, Jane, Lewis, John Arban, Garrison, Lehman H., and Carmichael, Theron. 2020. "Measured Lightcurves and Rotational Periods of 3122 Florence, 3830 Trelleborg, and (131077) 2000 YH105." Minor Planet Bulletin 47:3– 4.
ID: 158251
Type: article
Authors: Abrams, Natasha S.; Bieryla, Allyson; Gomez, Sebastian; Huang, Jane; Lewis, John Arban; Garrison, Lehman H.; Carmichael, Theron
Abstract: We determined the rotational periods of 3122 Florence, 3830 Trelleborg, and (131077) 2000 YH105 with the Harvard Clay Telescope and KeplerCam at the Fred L. Whipple Observatory. We found the rotational periods to be 2.3580 ± 0.0015 h, 17.059 ± 0.017 h, and 1.813 ± 0.00003 h, respectively. Our measurement of 3122 Florence's period agrees with Warner (2016), who reported 2.3580 ± 0.0002 h.
An Evolutionary Study of Volatile Chemistry in Protoplanetary DisksBergner, Jennifer B.Öberg, Karin I.Bergin, Edwin A.Andrews, Sean M.Blake, Geoffrey A.Carpenter, John M.Cleeves, L. IlsedoreGuzmán, Viviana V.Huang, JaneJørgensen, Jes K.Qi, ChunhuaSchwarz, Kamber R.Williams, Jonathan P.Wilner, David J.DOI: info:10.3847/1538-4357/ab9e71v. 89897
Bergner, Jennifer B., Öberg, Karin I., Bergin, Edwin A., Andrews, Sean M., Blake, Geoffrey A., Carpenter, John M., Cleeves, L. Ilsedore, Guzmán, Viviana V., Huang, Jane, Jørgensen, Jes K., Qi, Chunhua, Schwarz, Kamber R., Williams, Jonathan P., and Wilner, David J. 2020. "An Evolutionary Study of Volatile Chemistry in Protoplanetary Disks." The Astrophysical Journal 898:97. https://doi.org/10.3847/1538-4357/ab9e71
ID: 157660
Type: article
Authors: Bergner, Jennifer B.; Öberg, Karin I.; Bergin, Edwin A.; Andrews, Sean M.; Blake, Geoffrey A.; Carpenter, John M.; Cleeves, L. Ilsedore; Guzmán, Viviana V.; Huang, Jane; Jørgensen, Jes K.; Qi, Chunhua; Schwarz, Kamber R.; Williams, Jonathan P.; Wilner, David J.
Abstract: The volatile composition of a planet is determined by the inventory of gas and ice in the parent disk. The volatile chemistry in the disk is expected to evolve over time, though this evolution is poorly constrained observationally. We present Atacama Large Millimeter/submillimeter Array observations of C18O, C2H, and the isotopologues H13CN, HC15N, and DCN toward five Class 0/I disk candidates. Combined with a sample of 14 Class II disks presented in Bergner et al., this data set offers a view of volatile chemical evolution over the disk lifetime. Our estimates of C18O abundances are consistent with a rapid depletion of CO in the first ∼0.5-1 Myr of the disk lifetime. We do not see evidence that C2H and HCN formation are enhanced by CO depletion, possibly because the gas is already quite under-abundant in CO. Further CO depletion may actually hinder their production by limiting the gas-phase carbon supply. The embedded sources show several chemical differences compared to the Class II stage, which seem to arise from shielding of radiation by the envelope (impacting C2H formation and HC15N fractionation) and sublimation of ices from infalling material (impacting HCN and C18O abundances). Such chemical differences between Class 0/I and Class II sources may affect the volatile composition of planet-forming material at different stages in the disk lifetime.
Erratum: 'The Disk Substructures at High Angular Resolution Project (DSHARP). II. Characteristics of Annular Substructures' (2018, ApJL, 869, L42)Huang, JaneAndrews, Sean M.Dullemond, Cornelis P.Isella, AndreaPérez, Laura M.Guzmán, Viviana V.Öberg, Karin I.Zhu, ZhaohuanZhang, ShangjiaBai, Xue-NingBenisty, MyriamBirnstiel, TilmanCarpenter, John M.Hughes, A. MeredithRicci, LucaWeaver, ErikWilner, David J.DOI: info:10.3847/2041-8213/aba83bv. 898L57
Huang, Jane, Andrews, Sean M., Dullemond, Cornelis P., Isella, Andrea, Pérez, Laura M., Guzmán, Viviana V., Öberg, Karin I., Zhu, Zhaohuan, Zhang, Shangjia, Bai, Xue-Ning, Benisty, Myriam, Birnstiel, Tilman, Carpenter, John M., Hughes, A. Meredith, Ricci, Luca, Weaver, Erik, and Wilner, David J. 2020. "Erratum: "The Disk Substructures at High Angular Resolution Project (DSHARP). II. Characteristics of Annular Substructures" (2018, ApJL, 869, L42)." The Astrophysical Journal 898:L57. https://doi.org/10.3847/2041-8213/aba83b
ID: 157658
Type: article
Authors: Huang, Jane; Andrews, Sean M.; Dullemond, Cornelis P.; Isella, Andrea; Pérez, Laura M.; Guzmán, Viviana V.; Öberg, Karin I.; Zhu, Zhaohuan; Zhang, Shangjia; Bai, Xue-Ning; Benisty, Myriam; Birnstiel, Tilman; Carpenter, John M.; Hughes, A. Meredith; Ricci, Luca; Weaver, Erik; Wilner, David J.
A Multifrequency ALMA Characterization of Substructures in the GM Aur Protoplanetary DiskHuang, JaneAndrews, Sean M.Dullemond, Cornelis P.Öberg, Karin I.Qi, ChunhuaZhu, ZhaohuanBirnstiel, TilmanCarpenter, John M.Isella, AndreaMacías, EnriqueMcClure, Melissa K.Pérez, Laura M.Teague, RichardWilner, David J.Zhang, ShangjiaDOI: info:10.3847/1538-4357/ab711ev. 89148
Huang, Jane, Andrews, Sean M., Dullemond, Cornelis P., Öberg, Karin I., Qi, Chunhua, Zhu, Zhaohuan, Birnstiel, Tilman, Carpenter, John M., Isella, Andrea, Macías, Enrique, McClure, Melissa K., Pérez, Laura M., Teague, Richard, Wilner, David J., and Zhang, Shangjia. 2020. "A Multifrequency ALMA Characterization of Substructures in the GM Aur Protoplanetary Disk." The Astrophysical Journal 891:48. https://doi.org/10.3847/1538-4357/ab711e
ID: 156375
Type: article
Authors: Huang, Jane; Andrews, Sean M.; Dullemond, Cornelis P.; Öberg, Karin I.; Qi, Chunhua; Zhu, Zhaohuan; Birnstiel, Tilman; Carpenter, John M.; Isella, Andrea; Macías, Enrique; McClure, Melissa K.; Pérez, Laura M.; Teague, Richard; Wilner, David J.; Zhang, Shangjia
Abstract: The protoplanetary disk around the T Tauri star GM Aur was one of the first hypothesized to be in the midst of being cleared out by a forming planet. As a result, GM Aur has had an outsized influence on our understanding of disk structure and evolution. We present 1.1 and 2.1 mm ALMA continuum observations of the GM Aur disk at a resolution of ∼50 mas (∼8 au), as well as HCO+ J = 3 - 2 observations at a resolution of ∼100 mas. The dust continuum shows at least three rings atop faint, extended emission. Unresolved emission is detected at the center of the disk cavity at both wavelengths, likely due to a combination of dust and free-free emission. Compared to the 1.1 mm image, the 2.1 mm image shows a more pronounced "shoulder" near R ∼ 40 au, highlighting the utility of longer-wavelength observations for characterizing disk substructures. The spectral index α features strong radial variations, with minima near the emission peaks and maxima near the gaps. While low spectral indices have often been ascribed to grain growth and dust trapping, the optical depth of GM Aur's inner two emission rings renders their dust properties ambiguous. The gaps and outer disk (R > 100 au) are optically thin at both wavelengths. Meanwhile, the HCO+ emission indicates that the gas cavity is more compact than the dust cavity traced by the millimeter continuum, similar to other disks traditionally classified as "transitional."
Large-scale CO Spiral Arms and Complex Kinematics Associated with the T Tauri Star RU LupHuang, JaneAndrews, Sean M.Öberg, Karin I.Ansdell, MeganBenisty, MyriamCarpenter, John M.Isella, AndreaPérez, Laura M.Ricci, LucaWilliams, Jonathan P.Wilner, David J.Zhu, ZhaohuanDOI: info:10.3847/1538-4357/aba1e1v. 898140
Huang, Jane, Andrews, Sean M., Öberg, Karin I., Ansdell, Megan, Benisty, Myriam, Carpenter, John M., Isella, Andrea, Pérez, Laura M., Ricci, Luca, Williams, Jonathan P., Wilner, David J., and Zhu, Zhaohuan. 2020. "Large-scale CO Spiral Arms and Complex Kinematics Associated with the T Tauri Star RU Lup." The Astrophysical Journal 898:140. https://doi.org/10.3847/1538-4357/aba1e1
ID: 157659
Type: article
Authors: Huang, Jane; Andrews, Sean M.; Öberg, Karin I.; Ansdell, Megan; Benisty, Myriam; Carpenter, John M.; Isella, Andrea; Pérez, Laura M.; Ricci, Luca; Williams, Jonathan P.; Wilner, David J.; Zhu, Zhaohuan
Abstract: While protoplanetary disks often appear to be compact and well organized in millimeter continuum emission, CO spectral line observations are increasingly revealing complex behavior at large distances from the host star. We present deep Atacama Large Millimeter/submillimeter Array maps of the J = 2-1 transition of 12CO, 13CO, and C18O, as well as the J = 3-2 transition of DCO+, toward the T Tauri star RU Lup at a resolution of ∼0.3″ (∼50 au). The CO isotopologue emission traces four major components of the RU Lup system: a compact Keplerian disk with a radius of ∼120 au, a non-Keplerian "envelope-like" structure surrounding the disk and extending to ∼260 au from the star, at least five blueshifted spiral arms stretching up to 1000 au, and clumps outside the spiral arms located up to 1500 au in projection from RU Lup. We comment on potential explanations for RU Lup's peculiar gas morphology, including gravitational instability, accretion of material onto the disk, or perturbation by another star. RU Lup's extended non-Keplerian CO emission, elevated stellar accretion rate, and unusual photometric variability suggest that it could be a scaled-down Class II analog of the outbursting FU Ori systems.
A 3 mm Chemical Exploration of Small Organics in Class I YSOsLe Gal, RomaneÖberg, Karin I.Huang, JaneLaw, Charles J.Ménard, FrançoisLefloch, BertrandVastel, CharlotteLopez-Sepulcre, AnaFavre, CécileBianchi, EleonoraCeccarelli, CeciliaDOI: info:10.3847/1538-4357/ab9ebfv. 898131
Le Gal, Romane, Öberg, Karin I., Huang, Jane, Law, Charles J., Ménard, François, Lefloch, Bertrand, Vastel, Charlotte, Lopez-Sepulcre, Ana, Favre, Cécile, Bianchi, Eleonora, and Ceccarelli, Cecilia. 2020. "A 3 mm Chemical Exploration of Small Organics in Class I YSOs." The Astrophysical Journal 898:131. https://doi.org/10.3847/1538-4357/ab9ebf
ID: 158808
Type: article
Authors: Le Gal, Romane; Öberg, Karin I.; Huang, Jane; Law, Charles J.; Ménard, François; Lefloch, Bertrand; Vastel, Charlotte; Lopez-Sepulcre, Ana; Favre, Cécile; Bianchi, Eleonora; Ceccarelli, Cecilia
Abstract: There is mounting evidence that the composition and structure of planetary systems are intimately linked to their birth environments. During the past decade, several spectral surveys probed the chemistry of the earliest stages of star formation and late planet-forming disks. However, very little is known about the chemistry of intermediate protostellar stages, i.e., class I young stellar objects (YSOs), where planet formation may have already begun. We present here the first results of a 3 mm spectral survey performed with the IRAM 30 m telescope to investigate the chemistry of a sample of seven class I YSOs located in the Taurus star-forming region. These sources were selected to embrace the wide diversity identified for low-mass protostellar envelope and disk systems. We present detections and upper limits of 13 small (Natoms = 3) C, N, O, and S carriers-namely, CO, HCO+, HCN, HNC, CN, N2H+, C2H, CS, SO, HCS+, C2S, SO2, and OCS-and some of their D, 13C, 15N, 18O, 17O, and 34S isotopologues. Together, these species provide constraints on gas-phase C/N/O ratios, D and 15N fractionation, source temperature, and UV exposure, as well as the overall S chemistry. We find substantial evidence of chemical differentiation among our source sample, some of which can be traced back to class I physical parameters, such as the disk-to-envelope mass ratio (proxy for class I evolutionary stage), source luminosity, and UV field strength. Overall, these first results allow us to start investigating the astrochemistry of class I objects; however, interferometric observations are needed to differentiate envelope versus disk chemistry.
An Unbiased ALMA Spectral Survey of the LkCa 15 and MWC 480 Protoplanetary DisksLoomis, Ryan A.Öberg, Karin I.Andrews, Sean M.Bergin, EdwinBergner, JenniferBlake, Geoffrey A.Cleeves, L. IlsedoreCzekala, IanHuang, JaneLe Gal, RomaneMénard, FrancoisPegues, JamilaQi, ChunhuaWalsh, CatherineWilliams, Jonathan P.Wilner, David J.DOI: info:10.3847/1538-4357/ab7cc8v. 893101
Loomis, Ryan A., Öberg, Karin I., Andrews, Sean M., Bergin, Edwin, Bergner, Jennifer, Blake, Geoffrey A., Cleeves, L. Ilsedore, Czekala, Ian, Huang, Jane, Le Gal, Romane, Ménard, Francois, Pegues, Jamila, Qi, Chunhua, Walsh, Catherine, Williams, Jonathan P., and Wilner, David J. 2020. "An Unbiased ALMA Spectral Survey of the LkCa 15 and MWC 480 Protoplanetary Disks." The Astrophysical Journal 893:101. https://doi.org/10.3847/1538-4357/ab7cc8
ID: 157298
Type: article
Authors: Loomis, Ryan A.; Öberg, Karin I.; Andrews, Sean M.; Bergin, Edwin; Bergner, Jennifer; Blake, Geoffrey A.; Cleeves, L. Ilsedore; Czekala, Ian; Huang, Jane; Le Gal, Romane; Ménard, Francois; Pegues, Jamila; Qi, Chunhua; Walsh, Catherine; Williams, Jonathan P.; Wilner, David J.
Abstract: The volatile contents of protoplanetary disks both set the potential for planetary chemistry and provide valuable probes of defining disk system characteristics such as stellar mass, gas mass, ionization, and temperature structure. Current disk molecular inventories are fragmented, however, giving an incomplete picture: unbiased spectral line surveys are needed to assess the volatile content. We present here an overview of such a survey of the protoplanetary disks around the Herbig Ae star MWC 480 and the T Tauri star LkCa 15 in ALMA Band 7, spanning ∼36 GHz from 275 to 317 GHz and representing an order of magnitude increase in sensitivity over previous single-dish surveys. We detect 14 molecular species (including isotopologues), with five species (C34S, 13CS, H2CS, DNC, and C2D) detected for the first time in protoplanetary disks. Significant differences are observed in the molecular inventories of MWC 480 and LkCa 15, and we discuss how these results may be interpreted in light of the different physical conditions of these two disk systems.
An ALMA Survey of H2CO in Protoplanetary DisksPegues, JamilaÖberg, Karin I.Bergner, Jennifer B.Loomis, Ryan A.Qi, ChunhuaLe Gal, RomaneCleeves, L. IlsedoreGuzmán, Viviana V.Huang, JaneJørgensen, Jes K.Andrews, Sean M.Blake, Geoffrey A.Carpenter, John M.Schwarz, Kamber R.Williams, Jonathan P.Wilner, David J.DOI: info:10.3847/1538-4357/ab64d9v. 890142
Pegues, Jamila, Öberg, Karin I., Bergner, Jennifer B., Loomis, Ryan A., Qi, Chunhua, Le Gal, Romane, Cleeves, L. Ilsedore, Guzmán, Viviana V., Huang, Jane, Jørgensen, Jes K., Andrews, Sean M., Blake, Geoffrey A., Carpenter, John M., Schwarz, Kamber R., Williams, Jonathan P., and Wilner, David J. 2020. "An ALMA Survey of H2CO in Protoplanetary Disks." The Astrophysical Journal 890:142. https://doi.org/10.3847/1538-4357/ab64d9
ID: 155824
Type: article
Authors: Pegues, Jamila; Öberg, Karin I.; Bergner, Jennifer B.; Loomis, Ryan A.; Qi, Chunhua; Le Gal, Romane; Cleeves, L. Ilsedore; Guzmán, Viviana V.; Huang, Jane; Jørgensen, Jes K.; Andrews, Sean M.; Blake, Geoffrey A.; Carpenter, John M.; Schwarz, Kamber R.; Williams, Jonathan P.; Wilner, David J.
Abstract: H2CO is one of the most abundant organic molecules in protoplanetary disks and can serve as a precursor to more complex organic chemistry. We present an Atacama Large Millimeter/submillimeter Array survey of H2CO toward 15 disks covering a range of stellar spectral types, stellar ages, and dust continuum morphologies. H2CO is detected toward 13 disks and tentatively detected toward a fourteenth. We find both centrally peaked and centrally depressed emission morphologies, and half of the disks show ring-like structures at or beyond expected CO snowline locations. Together these morphologies suggest that H2CO in disks is commonly produced through both gas-phase and CO-ice-regulated grain-surface chemistry. We extract disk-averaged and azimuthally-averaged H2CO excitation temperatures and column densities for four disks with multiple H2CO line detections. The temperatures are between 20─50 K, with the exception of colder temperatures in the DM Tau disk. These temperatures suggest that H2CO emission in disks generally emerges from the warm molecular layer, with some contributions from the colder midplane. Applying the same H2CO excitation temperatures to all disks in the survey, we find that H2CO column densities span almost three orders of magnitude (∼5 × 1011─5 × 1014 cm−2). The column densities appear uncorrelated with disk size and stellar age, but Herbig Ae disks may have less H2CO compared to T Tauri disks, possibly because of less CO freeze-out. More H2CO observations toward Herbig Ae disks are needed to confirm this tentative trend, and to better constrain under which disk conditions H2CO and other oxygen-bearing organics efficiently form during planet formation.
Nine Localized Deviations from Keplerian Rotation in the DSHARP Circumstellar Disks: Kinematic Evidence for Protoplanets Carving the GapsPinte, C.Price, D. J.Ménard, F.Duchêne, G.Christiaens, V.Andrews, Sean M.Huang, JiashengHill, T.van der Plas, G.Perez, L. M.Isella, A.Boehler, Y.Dent, W. R. F.Mentiplay, D.Loomis, R. A.DOI: info:10.3847/2041-8213/ab6ddav. 890L9
Pinte, C., Price, D. J., Ménard, F., Duchêne, G., Christiaens, V., Andrews, Sean M., Huang, Jiasheng, Hill, T., van der Plas, G., Perez, L. M., Isella, A., Boehler, Y., Dent, W. R. F., Mentiplay, D., and Loomis, R. A. 2020. "Nine Localized Deviations from Keplerian Rotation in the DSHARP Circumstellar Disks: Kinematic Evidence for Protoplanets Carving the Gaps." The Astrophysical Journal 890:L9. https://doi.org/10.3847/2041-8213/ab6dda
ID: 156216
Type: article
Authors: Pinte, C.; Price, D. J.; Ménard, F.; Duchêne, G.; Christiaens, V.; Andrews, Sean M.; Huang, Jiasheng; Hill, T.; van der Plas, G.; Perez, L. M.; Isella, A.; Boehler, Y.; Dent, W. R. F.; Mentiplay, D.; Loomis, R. A.
Abstract: We present evidence for localized deviations from Keplerian rotation, i.e., velocity "kinks," in 8 of the 18 circumstellar disks observed by the DSHARP program: DoAr 25, Elias 2─27, GW Lup, HD 143006, HD 163296, IM Lup, Sz 129, and WaOph 6. Most of the kinks are detected over a small range in both radial extent and velocity, suggesting a planetary origin, but for some of them foreground contamination prevents us from measuring their spatial and velocity extent. Because of the DSHARP limited spectral resolution and signal to noise in the 12CO J = 2−1 line, as well as cloud contamination, the kinks are usually detected in only one spectral channel, and will require confirmation. The strongest circumstantial evidence for protoplanets in the absence of higher spectral resolution data and additional tracers is that, upon deprojection, we find that all of the candidate planets lie within a gap and/or at the end of a spiral detected in dust continuum emission. This suggests that a significant fraction of the dust gaps and spirals observed by Atacama Large Millimeter/submillimeter Array in disks are caused by embedded protoplanets.
Near-infrared Survey and Photometric Redshifts in the Extended GOODS-North FieldHsu, Li-TingLin, LihwaiDickinson, MarkYan, HaojingBau-Ching, HsiehWang, Wei-HaoLee, Chien-HsiuYan, Chi-HungScott, DouglasWillner, Steven P.Ouchi, MasamiAshby, Matthew L. N.Chen, Yi-WenDaddi, EmanueleElbaz, DavidFazio, Giovanni G.Foucaud, SebastienHuang, JiashengKoo, David C.Morrison, GlennOwen, FrazerPannella, MaurilioPope, AlexendraSimard, LucWang, Shiang-YuDOI: info:10.3847/1538-4357/aaf9a7v. 871233
Hsu, Li-Ting, Lin, Lihwai, Dickinson, Mark, Yan, Haojing, Bau-Ching, Hsieh, Wang, Wei-Hao, Lee, Chien-Hsiu, Yan, Chi-Hung, Scott, Douglas, Willner, Steven P., Ouchi, Masami, Ashby, Matthew L. N., Chen, Yi-Wen, Daddi, Emanuele, Elbaz, David, Fazio, Giovanni G., Foucaud, Sebastien, Huang, Jiasheng, Koo, David C., Morrison, Glenn, Owen, Frazer, Pannella, Maurilio, Pope, Alexendra, Simard, Luc, and Wang, Shiang-Yu. 2019. "Near-infrared Survey and Photometric Redshifts in the Extended GOODS-North Field." The Astrophysical Journal 871:233. https://doi.org/10.3847/1538-4357/aaf9a7
ID: 150499
Type: article
Authors: Hsu, Li-Ting; Lin, Lihwai; Dickinson, Mark; Yan, Haojing; Bau-Ching, Hsieh; Wang, Wei-Hao; Lee, Chien-Hsiu; Yan, Chi-Hung; Scott, Douglas; Willner, Steven P.; Ouchi, Masami; Ashby, Matthew L. N.; Chen, Yi-Wen; Daddi, Emanuele; Elbaz, David; Fazio, Giovanni G.; Foucaud, Sebastien; Huang, Jiasheng; Koo, David C.; Morrison, Glenn; Owen, Frazer; Pannella, Maurilio; Pope, Alexendra; Simard, Luc; Wang, Shiang-Yu
Abstract: We present deep J- and H-band images in the extended Great Observatories Origins Deep Survey-North field covering an area of 0.22 deg2. The observations were taken using WIRCam on the 3.6 m Canada–France–Hawaii Telescope. Together with the reprocessed K s-band image, the 5σ limiting AB magnitudes (in 2″ diameter apertures) are 24.7, 24.2, and 24.4 AB mag in the J, H, and K s bands, respectively. We also release a multiband photometry and photometric redshift catalog containing 93,598 sources. For non-X-ray sources, we obtained a photometric redshift accuracy σ NMAD = 0.036 with an outlier fraction η = 7.3%. For X-ray sources, which are mainly active galactic nuclei (AGNs), we cross-matched our catalog with the updated 2M-CDFN X-ray catalog from Xue et al. and found that 658 out of 683 X-ray sources have counterparts. GALEX UV data are included in the photometric redshift computation for the X-ray sources to give σ NMAD = 0.040 with η = 10.5%. Our approach yields more accurate photometric redshift estimates compared to previous works in this field. In particular, by adopting AGN–galaxy hybrid templates, our approach delivers photometric redshifts for the X-ray counterparts with fewer outliers compared to the 3D-Hubble Space Telescope catalog, which fit these sources with galaxy-only templates.
Spiral Structure in the Gas Disk of TW HyaTeague, RichardBae, JaehanHuang, JaneBergin, Edwin A.DOI: info:10.3847/2041-8213/ab4a83v. 884L56
Teague, Richard, Bae, Jaehan, Huang, Jane, and Bergin, Edwin A. 2019. "Spiral Structure in the Gas Disk of TW Hya." The Astrophysical Journal 884:L56. https://doi.org/10.3847/2041-8213/ab4a83
ID: 154723
Type: article
Authors: Teague, Richard; Bae, Jaehan; Huang, Jane; Bergin, Edwin A.
Abstract: We report the detection of spiral substructure in both the gas velocity and temperature structure of the disk around TW Hya, suggestive of planet-disk interactions with an unseen planet. Perturbations from Keplerian rotation tracing out a spiral pattern are observed in the SE of the disk, while significant azimuthal perturbations in the gas temperature are seen in the outer disk, outside 90 au, extending the full azimuth of the disk. The deviation in velocity is either ∆v ϕ /v kep ̃ 0.1 or ∆v z /v kep ̃ 0.01 depending on whether the perturbation is in the rotational or vertical direction, while radial perturbations can be ruled out. Deviations in the gas temperature are ±4 K about the azimuthally averaged profile, equivalent to deviations of ∆T gas/T gas ̃ 0.05. Assuming all three structures can be described by an Archimedean spiral, measurements of the pitch angles of both velocity and temperature spirals show a radially decreasing trend for all three, ranging from 9° at 70 au, dropping to 3° at 200 au. Such low pitch- angled spirals are not readily explained through the wake of an embedded planet in the location of previously reported at 94 au, but rather require a launching mechanism that results in much more tightly wound spirals. Molecular emission tracing distinct heights in the disk is required to accurately distinguish between spiral launching mechanisms.
One Solution to the Mass Budget Problem for Planet Formation: Optically Thick Disks with Dust ScatteringZhu, ZhaohuanZhang, ShangjiaJiang, Yan-FeiKataoka, AkimasaBirnstiel, TilmanDullemond, Cornelis P.Andrews, Sean M.Huang, JanePérez, Laura M.Carpenter, John M.Bai, Xue-NingWilner, David J.Ricci, LucaDOI: info:10.3847/2041-8213/ab1f8cv. 877L18
Zhu, Zhaohuan, Zhang, Shangjia, Jiang, Yan-Fei, Kataoka, Akimasa, Birnstiel, Tilman, Dullemond, Cornelis P., Andrews, Sean M., Huang, Jane, Pérez, Laura M., Carpenter, John M., Bai, Xue-Ning, Wilner, David J., and Ricci, Luca. 2019. "One Solution to the Mass Budget Problem for Planet Formation: Optically Thick Disks with Dust Scattering." Astrophysical Journal Letters 877:L18. https://doi.org/10.3847/2041-8213/ab1f8c
ID: 152927
Type: article
Authors: Zhu, Zhaohuan; Zhang, Shangjia; Jiang, Yan-Fei; Kataoka, Akimasa; Birnstiel, Tilman; Dullemond, Cornelis P.; Andrews, Sean M.; Huang, Jane; Pérez, Laura M.; Carpenter, John M.; Bai, Xue-Ning; Wilner, David J.; Ricci, Luca
Abstract: Atacama Large Millimeter Array (ALMA) surveys have suggested that the dust in Class II disks may not be enough to explain the averaged solid mass in exoplanets, under the assumption that the mm disk continuum emission is optically thin. This optically thin assumption seems to be supported by recent Disk Substructures at High Angular Resolution Project (DSHARP) observations where the measured optical depths are mostly less than one. However, we point out that dust scattering can considerably reduce the emission from an optically thick region. If that scattering is ignored, an optically thick disk with scattering can be misidentified as an optically thin disk. Dust scattering in more inclined disks can reduce the intensity even further, making the disk look even fainter. The measured optical depth of ∼0.6 in several DSHARP disks can be naturally explained by optically thick dust with an albedo of ∼0.9 at 1.25 mm. Using the DSHARP opacity, this albedo corresponds to a dust population with the maximum grain size (s max) of 0.1–1 mm. For optically thick scattering disks, the measured spectral index α can be either larger or smaller than 2 depending on whether the dust albedo increases or decreases with wavelength. We describe how this optically thick scattering scenario could explain the observed scaling between submm continuum sizes and luminosities, and might help ease the tension between the dust size constraints from polarization and dust continuum measurements. We suggest that a significant amount of disk mass can be hidden from ALMA observations and longer wavelength observations (e.g., Very Large Array or Square Kilometre Array) are desired to probe the dust mass in disks.
The Disk Substructures at High Angular Resolution Project (DSHARP). I. Motivation, Sample, Calibration, and OverviewAndrews, Sean M.Huang, JanePérez, Laura M.Isella, AndreaDullemond, Cornelis P.Kurtovic, Nicolás T.Guzmán, Viviana V.Carpenter, John M.Wilner, David J.Zhang, ShangjiaZhu, ZhaohuanBirnstiel, TilmanBai, Xue-NingBenisty, MyriamHughes, A. MeredithÖberg, Karin I.Ricci, LucaDOI: info:10.3847/2041-8213/aaf741v. 869L41
Andrews, Sean M., Huang, Jane, Pérez, Laura M., Isella, Andrea, Dullemond, Cornelis P., Kurtovic, Nicolás T., Guzmán, Viviana V., Carpenter, John M., Wilner, David J., Zhang, Shangjia, Zhu, Zhaohuan, Birnstiel, Tilman, Bai, Xue-Ning, Benisty, Myriam, Hughes, A. Meredith, Öberg, Karin I., and Ricci, Luca. 2018. "The Disk Substructures at High Angular Resolution Project (DSHARP). I. Motivation, Sample, Calibration, and Overview." Astrophysical Journal Letters 869:L41. https://doi.org/10.3847/2041-8213/aaf741
ID: 150171
Type: article
Authors: Andrews, Sean M.; Huang, Jane; Pérez, Laura M.; Isella, Andrea; Dullemond, Cornelis P.; Kurtovic, Nicolás T.; Guzmán, Viviana V.; Carpenter, John M.; Wilner, David J.; Zhang, Shangjia; Zhu, Zhaohuan; Birnstiel, Tilman; Bai, Xue-Ning; Benisty, Myriam; Hughes, A. Meredith; Öberg, Karin I.; Ricci, Luca
Abstract: We introduce the Disk Substructures at High Angular Resolution Project (DSHARP), one of the initial Large Programs conducted with the Atacama Large Millimeter/submillimeter Array (ALMA). The primary goal of DSHARP is to find and characterize substructures in the spatial distributions of solid particles for a sample of 20 nearby protoplanetary disks, using very high resolution (∼0.″035, or 5 au, FWHM) observations of their 240 GHz (1.25 mm) continuum emission. These data provide a first homogeneous look at the small-scale features in disks that are directly relevant to the planet formation process, quantifying their prevalence, morphologies, spatial scales, spacings, symmetry, and amplitudes, for targets with a variety of disk and stellar host properties. We find that these substructures are ubiquitous in this sample of large, bright disks. They are most frequently manifested as concentric, narrow emission rings and depleted gaps, although large-scale spiral patterns and small arc-shaped azimuthal asymmetries are also present in some cases. These substructures are found at a wide range of disk radii (from a few astronomical units to more than 100 au), are usually compact (≲10 au), and show a wide range of amplitudes (brightness contrasts). Here we discuss the motivation for the project, describe the survey design and the sample properties, detail the observations and data calibration, highlight some basic results, and provide a general overview of the key conclusions that are presented in more detail in a series of accompanying articles. The DSHARP data—including visibilities, images, calibration scripts, and more—are released for community use at https://almascience.org/alma-data/lp/DSHARP.
The Disk Substructures at High Angular Resolution Project (DSHARP). V. Interpreting ALMA Maps of Protoplanetary Disks in Terms of a Dust ModelBirnstiel, TilmanDullemond, Cornelis P.Zhu, ZhaohuanAndrews, Sean M.Bai, Xue-NingWilner, David J.Carpenter, John M.Huang, JaneIsella, AndreaBenisty, MyriamPérez, Laura M.Zhang, ShangjiaDOI: info:10.3847/2041-8213/aaf743v. 869L45
Birnstiel, Tilman, Dullemond, Cornelis P., Zhu, Zhaohuan, Andrews, Sean M., Bai, Xue-Ning, Wilner, David J., Carpenter, John M., Huang, Jane, Isella, Andrea, Benisty, Myriam, Pérez, Laura M., and Zhang, Shangjia. 2018. "The Disk Substructures at High Angular Resolution Project (DSHARP). V. Interpreting ALMA Maps of Protoplanetary Disks in Terms of a Dust Model." Astrophysical Journal Letters 869:L45. https://doi.org/10.3847/2041-8213/aaf743
ID: 150174
Type: article
Authors: Birnstiel, Tilman; Dullemond, Cornelis P.; Zhu, Zhaohuan; Andrews, Sean M.; Bai, Xue-Ning; Wilner, David J.; Carpenter, John M.; Huang, Jane; Isella, Andrea; Benisty, Myriam; Pérez, Laura M.; Zhang, Shangjia
Abstract: The Disk Substructures at High Angular Resolution Project (DSHARP) is the largest homogeneous high-resolution (∼0.″035, or ∼5 au) disk continuum imaging survey with the Atacama Large Millimeter/submillimeter Array (ALMA) so far. In the coming years, many more disks will be mapped with ALMA at similar resolution. Interpreting the results in terms of the properties and quantities of the emitting dusty material is, however, a very non-trivial task. This is in part due to the uncertainty in the dust opacities, an uncertainty that is not likely to be resolved any time soon. It is also partly due to the fact that, as the DSHARP survey has shown, these disk often contain regions of intermediate to high optical depth, even at millimeter wavelengths and at relatively large radius in the disk. This makes the interpretation challenging, in particular if the grains are large and have a large albedo. On the other hand, the highly structured features seen in the DSHARP survey, of which strong indications were already seen in earlier observations, provide a unique opportunity to study the dust growth and dynamics. To provide continuity within the DSHARP project, its follow-up projects, and projects by other teams interested in these data, we present here the methods and opacity choices used within the DSHARP collaboration to link the measured intensity I ν to dust surface density Σ d .
Constraining Gas-phase Carbon, Oxygen, and Nitrogen in the IM Lup Protoplanetary DiskCleeves, L. IlsedoreÖberg, Karin I.Wilner, David J.Huang, JaneLoomis, Ryan A.Andrews, Sean M.Guzman, V. V.DOI: info:10.3847/1538-4357/aade96v. 865155
Cleeves, L. Ilsedore, Öberg, Karin I., Wilner, David J., Huang, Jane, Loomis, Ryan A., Andrews, Sean M., and Guzman, V. V. 2018. "Constraining Gas-phase Carbon, Oxygen, and Nitrogen in the IM Lup Protoplanetary Disk." The Astrophysical Journal 865:155. https://doi.org/10.3847/1538-4357/aade96
ID: 149393
Type: article
Authors: Cleeves, L. Ilsedore; Öberg, Karin I.; Wilner, David J.; Huang, Jane; Loomis, Ryan A.; Andrews, Sean M.; Guzman, V. V.
Abstract: We present new constraints on gas-phase C, N, and O abundances in the molecular layer of the IM Lup protoplanetary disk. Building on previous physical and chemical modeling of this disk, we use new ALMA observations of C2H to constrain the C/O ratio in the molecular layer to be ∼0.8, i.e., higher than the solar value of ∼0.54. We use archival ALMA observations of HCN and H13CN to show that no depletion of N is required (assuming an interstellar abundance of 7.5 × 10‑5 per H). These results suggest that an appreciable fraction of O is sequestered in water ice in large grains settled to the disk midplane. Similarly, a fraction of the available C is locked up in less volatile molecules. By contrast, N remains largely unprocessed, likely as N2. This pattern of depletion suggests the presence of true abundance variations in this disk, and not a simple overall depletion of gas mass. If these results hold more generally, then combined CO, C2H, and HCN observations of disks may provide a promising path for constraining gas-phase C/O and N/O during planet-formation. Together, these tracers offer the opportunity to link the volatile compositions of disks to the atmospheres of planets formed from them.
The Disk Substructures at High Angular Resolution Project (DSHARP). VI. Dust Trapping in Thin-ringed Protoplanetary DisksDullemond, Cornelis P.Birnstiel, TilmanHuang, JaneKurtovic, Nicolás T.Andrews, Sean M.Guzmán, Viviana V.Pérez, Laura M.Isella, AndreaZhu, ZhaohuanBenisty, MyriamWilner, David J.Bai, Xue-NingCarpenter, John M.Zhang, ShangjiaRicci, LucaDOI: info:10.3847/2041-8213/aaf742v. 869L46
Dullemond, Cornelis P., Birnstiel, Tilman, Huang, Jane, Kurtovic, Nicolás T., Andrews, Sean M., Guzmán, Viviana V., Pérez, Laura M., Isella, Andrea, Zhu, Zhaohuan, Benisty, Myriam, Wilner, David J., Bai, Xue-Ning, Carpenter, John M., Zhang, Shangjia, and Ricci, Luca. 2018. "The Disk Substructures at High Angular Resolution Project (DSHARP). VI. Dust Trapping in Thin-ringed Protoplanetary Disks." Astrophysical Journal Letters 869:L46. https://doi.org/10.3847/2041-8213/aaf742
ID: 150186
Type: article
Authors: Dullemond, Cornelis P.; Birnstiel, Tilman; Huang, Jane; Kurtovic, Nicolás T.; Andrews, Sean M.; Guzmán, Viviana V.; Pérez, Laura M.; Isella, Andrea; Zhu, Zhaohuan; Benisty, Myriam; Wilner, David J.; Bai, Xue-Ning; Carpenter, John M.; Zhang, Shangjia; Ricci, Luca
Abstract: A large fraction of the protoplanetary disks observed with ALMA display multiple well-defined and nearly perfectly circular rings in the continuum, in many cases with substantial peak-to-valley contrast. The DSHARP campaign shows that several of these rings are very narrow in radial extent. In this Letter we test the hypothesis that these dust rings are caused by dust trapping in radial pressure bumps, and if confirmed, put constraints on the physics of the dust trapping mechanism. We model this process analytically in 1D, assuming axisymmetry. By comparing this model to the data, we find that all rings are consistent with dust trapping. Based on a plausible model of the dust temperature we find that several rings are narrower than the pressure scale height, providing strong evidence for dust trapping. The rings have peak absorption optical depth in the range between 0.2 and 0.5. The dust masses stored in each of these rings is of the order of tens of Earth masses, though much ambiguity remains due to the uncertainty of the dust opacities. The dust rings are dense enough to potentially trigger the streaming instability, but our analysis cannot give proof of this mechanism actually operating. Our results show, however, that the combination of very low {α }turb}\ll 5× {10}-4 and very large grains {a}grain}\gg 0.1 {cm} can be excluded by the data for all the rings studied in this Letter.
The Disk Substructures at High Angular Resolution Program (DSHARP). VIII. The Rich Ringed Substructures in the AS 209 DiskGuzmán, Viviana V.Huang, JaneAndrews, Sean M.Isella, AndreaPérez, Laura M.Carpenter, John M.Dullemond, Cornelis P.Ricci, LucaBirnstiel, TilmanZhang, ShangjiaZhu, ZhaohuanBai, Xue-NingBenisty, MyriamÖberg, Karin I.Wilner, David J.DOI: info:10.3847/2041-8213/aaedaev. 869L48
Guzmán, Viviana V., Huang, Jane, Andrews, Sean M., Isella, Andrea, Pérez, Laura M., Carpenter, John M., Dullemond, Cornelis P., Ricci, Luca, Birnstiel, Tilman, Zhang, Shangjia, Zhu, Zhaohuan, Bai, Xue-Ning, Benisty, Myriam, Öberg, Karin I., and Wilner, David J. 2018. "The Disk Substructures at High Angular Resolution Program (DSHARP). VIII. The Rich Ringed Substructures in the AS 209 Disk." Astrophysical Journal Letters 869:L48. https://doi.org/10.3847/2041-8213/aaedae
ID: 150193
Type: article
Authors: Guzmán, Viviana V.; Huang, Jane; Andrews, Sean M.; Isella, Andrea; Pérez, Laura M.; Carpenter, John M.; Dullemond, Cornelis P.; Ricci, Luca; Birnstiel, Tilman; Zhang, Shangjia; Zhu, Zhaohuan; Bai, Xue-Ning; Benisty, Myriam; Öberg, Karin I.; Wilner, David J.
Abstract: We present a detailed analysis of the high angular resolution (0.″037, corresponding to 5 au) observations of the 1.25 mm continuum and 12CO 2 ‑ 1 emission from the disk around the T Tauri star AS 209. AS 209 hosts one of the most unusual disks from the Disk Substructures at High Angular Resolution Project sample, the first high angular resolution Atacama Large Millimeter Array survey of disks, as nearly all of the emission can be explained with concentric Gaussian rings. In particular, the dust emission consists of a series of narrow and closely spaced rings in the inner ∼60 au, two well-separated bright rings in the outer disk, centered at 74 and 120 au, and at least two fainter emission features at 90 and 130 au. We model the visibilities with a parametric representation of the radial surface brightness profile, consisting of a central core and seven concentric Gaussian rings. Recent hydrodynamical simulations of low-viscosity disks show that super-Earth planets can produce the multiple gaps seen in AS 209 millimeter continuum emission. The 12CO line emission is centrally peaked and extends out to ∼300 au, much farther than the millimeter dust emission. We find axisymmetric, localized deficits of CO emission around four distinct radii, near 45, 75, 120, and 210 au. The outermost gap is located well beyond the edge of the millimeter dust emission, and therefore cannot be due to dust opacity and must be caused by a genuine CO surface density reduction, due either to chemical effects or depletion of the overall gas content.