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Showing 1-20 of about 42 results.
RELICS: A Very Large (θE ∼ 40″) Cluster Lens-RXC J0032.1+1808Acebron, AnaZitrin, AdiCoe, DanMahler, GuillaumeSharon, KerenOguri, MasamuneBradač, MarušaBradley, Larry D.Frye, BrendaForman, Christine J.Strait, VictoriaSu, YuanyuanUmetsu, KeiichiAndrade-Santos, FelipeAvila, Roberto J.Carrasco, DanielaCerny, CatherineCzakon, Nicole G.Dawson, William A.Fox, CarterHoag, Austin T.Huang, Kuang-HanJohnson, Traci L.Kikuchihara, ShotaroLam, DanielLovisari, LorenzoMainali, RameshNonino, MarioOesch, Pascal A.Ogaz, SaraOuchi, MasamiPast, MatthewPaterno-Mahler, RachelPeterson, AveryRyan, Russell E.Salmon, BrettStark, Daniel P.Toft, SuneTrenti, MicheleVulcani, BenedettaWelch, BrianDOI: info:10.3847/1538-4357/ab929dv. 8986
Acebron, Ana, Zitrin, Adi, Coe, Dan, Mahler, Guillaume, Sharon, Keren, Oguri, Masamune, Bradač, Maruša, Bradley, Larry D., Frye, Brenda, Forman, Christine J., Strait, Victoria, Su, Yuanyuan, Umetsu, Keiichi, Andrade-Santos, Felipe, Avila, Roberto J., Carrasco, Daniela, Cerny, Catherine, Czakon, Nicole G., Dawson, William A., Fox, Carter, Hoag, Austin T., Huang, Kuang-Han, Johnson, Traci L., Kikuchihara, Shotaro, Lam, Daniel et al. 2020. "RELICS: A Very Large (θE ∼ 40″) Cluster Lens-RXC J0032.1+1808." The Astrophysical Journal 898:6. https://doi.org/10.3847/1538-4357/ab929d
ID: 157836
Type: article
Authors: Acebron, Ana; Zitrin, Adi; Coe, Dan; Mahler, Guillaume; Sharon, Keren; Oguri, Masamune; Bradač, Maruša; Bradley, Larry D.; Frye, Brenda; Forman, Christine J.; Strait, Victoria; Su, Yuanyuan; Umetsu, Keiichi; Andrade-Santos, Felipe; Avila, Roberto J.; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Fox, Carter; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Kikuchihara, Shotaro; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Nonino, Mario; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Stark, Daniel P.; Toft, Sune; Trenti, Michele; Vulcani, Benedetta; Welch, Brian
Abstract: Extensive surveys with the Hubble Space Telescope over the past decade, targeting some of the most massive clusters in the sky, have uncovered dozens of galaxy cluster strong lenses. The massive cluster strong-lens scale is typically θE ∼ 10″ to ∼30″-35″, with only a handful of clusters known with Einstein radii θE ∼ 40″ or above (for zsource = 2, nominally). Here we report another very large cluster lens, RXC J0032.1+1808 (z = 0.3956), the second-richest cluster in the redMapper cluster catalog and the 85th most massive cluster in the Planck Sunyaev-Zel'dovich catalog. With our light-traces-mass and fully parametric approaches, we construct strong-lensing models based on 18 multiple images of five background galaxies newly identified in the Hubble data, mainly from the Reionization Lensing Cluster Survey (RELICS), in addition to a known sextuply imaged system in this cluster. Furthermore, we compare these models to Lenstool and GLAFIC models that were produced independently as part of the RELICS program. All models reveal a large effective Einstein radius of θE ≃ 40″ (zsource = 2), owing to the obvious concentration of substructures near the cluster center. Although RXC J0032.1+1808 has a very large critical area and high lensing strength, only three magnified high-redshift candidates are found within the field targeted by RELICS. Nevertheless, we expect many more high-redshift candidates will be seen in wider and deeper observations with Hubble or the James Webb Space Telescope. Finally, the comparison between several algorithms demonstrates that the total error budget is largely dominated by systematic uncertainties.
Type: article
Authors: Acebron, Ana; Zitrin, Adi; Coe, Dan; Mahler, Guillaume; Sharon, Keren; Oguri, Masamune; Bradač, Maruša; Bradley, Larry D.; Frye, Brenda; Forman, Christine J.; Strait, Victoria; Su, Yuanyuan; Umetsu, Keiichi; Andrade-Santos, Felipe; Avila, Roberto J.; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Fox, Carter; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Kikuchihara, Shotaro; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Nonino, Mario; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Stark, Daniel P.; Toft, Sune; Trenti, Michele; Vulcani, Benedetta; Welch, Brian
Abstract: Extensive surveys with the Hubble Space Telescope over the past decade, targeting some of the most massive clusters in the sky, have uncovered dozens of galaxy cluster strong lenses. The massive cluster strong-lens scale is typically θE ∼ 10″ to ∼30″-35″, with only a handful of clusters known with Einstein radii θE ∼ 40″ or above (for zsource = 2, nominally). Here we report another very large cluster lens, RXC J0032.1+1808 (z = 0.3956), the second-richest cluster in the redMapper cluster catalog and the 85th most massive cluster in the Planck Sunyaev-Zel'dovich catalog. With our light-traces-mass and fully parametric approaches, we construct strong-lensing models based on 18 multiple images of five background galaxies newly identified in the Hubble data, mainly from the Reionization Lensing Cluster Survey (RELICS), in addition to a known sextuply imaged system in this cluster. Furthermore, we compare these models to Lenstool and GLAFIC models that were produced independently as part of the RELICS program. All models reveal a large effective Einstein radius of θE ≃ 40″ (zsource = 2), owing to the obvious concentration of substructures near the cluster center. Although RXC J0032.1+1808 has a very large critical area and high lensing strength, only three magnified high-redshift candidates are found within the field targeted by RELICS. Nevertheless, we expect many more high-redshift candidates will be seen in wider and deeper observations with Hubble or the James Webb Space Telescope. Finally, the comparison between several algorithms demonstrates that the total error budget is largely dominated by systematic uncertainties.
Comparing different mass estimators for a large subsample of the Planck-ESZ clustersLovisari, LorenzoEttori, S.Sereno, M.Schellenberger, GerritForman, William R.Andrade-Santos, FelipeJones, C.DOI: info:10.1051/0004-6361/202038718v. 644A78
Lovisari, Lorenzo, Ettori, S., Sereno, M., Schellenberger, Gerrit, Forman, William R., Andrade-Santos, Felipe, and Jones, C. 2020. "Comparing different mass estimators for a large subsample of the Planck-ESZ clusters." Astronomy and Astrophysics 644:A78. https://doi.org/10.1051/0004-6361/202038718
ID: 158594
Type: article
Authors: Lovisari, Lorenzo; Ettori, S.; Sereno, M.; Schellenberger, Gerrit; Forman, William R.; Andrade-Santos, Felipe; Jones, C.
Abstract: Context. Total mass is arguably the most fundamental property for cosmological studies with galaxy clusters. The individual cluster masses can be obtained with different methods, each with its own biases and limitations. Systematic differences in mass measurements can strongly impact the determination of the hydrostatic bias and of the mass-observable relations, key requirements of many cluster abundance studies.
Aims: We investigate the present differences in the mass estimates obtained through independent X-ray, weak-lensing, and dynamical studies using a large subsample of the Planck-ESZ clusters. We also discuss the implications for mass bias analyses.
Methods: After assessing the systematic differences in the X-ray-derived masses reported by distinct groups, we examine the mass estimates obtained with independent methods and quantify the differences as the mean ratio 1-b = MHE/MWL, dyn, where HE refers to hydrostatic masses obtained from X-ray observations, WL refers to the results of weak-lensing measurements, and dyn refers to the mass estimates either from velocity dispersion or from the caustic technique. So defined, the 1-b parameter includes all possible astrophysical, observational, and methodological biases in one single value.
Results: Recent X-ray masses reported by independent groups show average differences smaller than ˜10%, posing a strong limit on the systematics that can be ascribed to the differences in the X-ray analysis when studying the hydrostatic bias. The mean ratio between our X-ray masses and the weak-lensing masses in the LC2-single catalog is 1-b = 0.74 ± 0.06, which corresponds to a mass bias of 26 ± 6%, a value insufficient to reconcile the Planck cluster abundance and cosmic microwave background results. However, the mean mass ratios inferred from the WL masses of different projects vary by a large amount, with APEX-SZ showing a bias consistent with zero (1-b = 1.02 ± 0.12), LoCuSS and CCCP/MENeaCS showing a significant difference (1-b = 0.76 ± 0.09 and 1-b = 0.77 ± 0.10, respectively), and WtG pointing to the largest deviation (1-b = 0.61 ± 0.12), which would substantially reduce the tension between the Planck results. Because of small differences between our M - YX relation and the one used by the Planck collaboration, our X-ray masses are on average 7% lower (4% at the same physical radius) than the Planck masses and can further reduce the required bias. At odds with the WL results, the dynamical mass measurements show better agreement with the X-ray hydrostatic masses, although there are significant differences when relaxed or disturbed clusters are used. However, the comparison is currently limited by the small sample sizes. Conclisions. The systematic differences between total masses obtained with recent independent X-ray analyses are smaller than those found in previous studies. This shifts the focus to WL and dynamical studies for a better convergence of the level of mass bias. However, the ratios obtained using different mass estimators suggest that there are still systematics that are not accounted for in all the techniques used to recover cluster masses. This prevents the determination of firm constraints on the level of hydrostatic mass bias in galaxy clusters.
Type: article
Authors: Lovisari, Lorenzo; Ettori, S.; Sereno, M.; Schellenberger, Gerrit; Forman, William R.; Andrade-Santos, Felipe; Jones, C.
Abstract: Context. Total mass is arguably the most fundamental property for cosmological studies with galaxy clusters. The individual cluster masses can be obtained with different methods, each with its own biases and limitations. Systematic differences in mass measurements can strongly impact the determination of the hydrostatic bias and of the mass-observable relations, key requirements of many cluster abundance studies.
Aims: We investigate the present differences in the mass estimates obtained through independent X-ray, weak-lensing, and dynamical studies using a large subsample of the Planck-ESZ clusters. We also discuss the implications for mass bias analyses.
Methods: After assessing the systematic differences in the X-ray-derived masses reported by distinct groups, we examine the mass estimates obtained with independent methods and quantify the differences as the mean ratio 1-b = MHE/MWL, dyn, where HE refers to hydrostatic masses obtained from X-ray observations, WL refers to the results of weak-lensing measurements, and dyn refers to the mass estimates either from velocity dispersion or from the caustic technique. So defined, the 1-b parameter includes all possible astrophysical, observational, and methodological biases in one single value.
Results: Recent X-ray masses reported by independent groups show average differences smaller than ˜10%, posing a strong limit on the systematics that can be ascribed to the differences in the X-ray analysis when studying the hydrostatic bias. The mean ratio between our X-ray masses and the weak-lensing masses in the LC2-single catalog is 1-b = 0.74 ± 0.06, which corresponds to a mass bias of 26 ± 6%, a value insufficient to reconcile the Planck cluster abundance and cosmic microwave background results. However, the mean mass ratios inferred from the WL masses of different projects vary by a large amount, with APEX-SZ showing a bias consistent with zero (1-b = 1.02 ± 0.12), LoCuSS and CCCP/MENeaCS showing a significant difference (1-b = 0.76 ± 0.09 and 1-b = 0.77 ± 0.10, respectively), and WtG pointing to the largest deviation (1-b = 0.61 ± 0.12), which would substantially reduce the tension between the Planck results. Because of small differences between our M - YX relation and the one used by the Planck collaboration, our X-ray masses are on average 7% lower (4% at the same physical radius) than the Planck masses and can further reduce the required bias. At odds with the WL results, the dynamical mass measurements show better agreement with the X-ray hydrostatic masses, although there are significant differences when relaxed or disturbed clusters are used. However, the comparison is currently limited by the small sample sizes. Conclisions. The systematic differences between total masses obtained with recent independent X-ray analyses are smaller than those found in previous studies. This shifts the focus to WL and dynamical studies for a better convergence of the level of mass bias. However, the ratios obtained using different mass estimators suggest that there are still systematics that are not accounted for in all the techniques used to recover cluster masses. This prevents the determination of firm constraints on the level of hydrostatic mass bias in galaxy clusters.
X-Ray Scaling Relations for a Representative Sample of Planck-selected Clusters Observed with XMM-NewtonLovisari, LorenzoSchellenberger, GerritSereno, MauroEttori, StefanoPratt, Gabriel W.Forman, William R.Jones, ChristineAndrade-Santos, FelipeRandall, ScottKraft, RalphDOI: info:10.3847/1538-4357/ab7997v. 892102
Lovisari, Lorenzo, Schellenberger, Gerrit, Sereno, Mauro, Ettori, Stefano, Pratt, Gabriel W., Forman, William R., Jones, Christine, Andrade-Santos, Felipe, Randall, Scott, and Kraft, Ralph. 2020. "X-Ray Scaling Relations for a Representative Sample of Planck-selected Clusters Observed with XMM-Newton." The Astrophysical Journal 892:102. https://doi.org/10.3847/1538-4357/ab7997
ID: 157289
Type: article
Authors: Lovisari, Lorenzo; Schellenberger, Gerrit; Sereno, Mauro; Ettori, Stefano; Pratt, Gabriel W.; Forman, William R.; Jones, Christine; Andrade-Santos, Felipe; Randall, Scott; Kraft, Ralph
Abstract: We report the scaling relations derived by fitting the X-ray parameters determined from analyzing the XMM-Newton observations of 120 galaxy clusters in the Planck Early Sunyaev-Zel'dovich (SZ) sample spanning the redshift range of 0.059 tot and L-T relations determined for different samples. Mtot-T, Mtot-YX, and Mtot-Mgas relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution ( relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution (tot-T relation) of the scaling relations. For the first time, we find significant evolution (>3σ) of the Mtot-T relation, pointing to an increase of the kinetic- to-thermal energy ratio with redshift. This is consistent with a scenario in which higher-redshift clusters are on average more disturbed than their lower-redshift counterparts.
Type: article
Authors: Lovisari, Lorenzo; Schellenberger, Gerrit; Sereno, Mauro; Ettori, Stefano; Pratt, Gabriel W.; Forman, William R.; Jones, Christine; Andrade-Santos, Felipe; Randall, Scott; Kraft, Ralph
Abstract: We report the scaling relations derived by fitting the X-ray parameters determined from analyzing the XMM-Newton observations of 120 galaxy clusters in the Planck Early Sunyaev-Zel'dovich (SZ) sample spanning the redshift range of 0.059 tot and L-T relations determined for different samples. Mtot-T, Mtot-YX, and Mtot-Mgas relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution ( relations show little dependence on the dynamical state of the clusters, but the normalizations of these relations may depend on the mass range investigated. Although most of the clusters investigated in this work reside at relatively low redshift, the fits prefer values of γ, the parameter accounting for the redshift evolution, different from the self-similar predictions. This suggests an evolution (tot-T relation) of the scaling relations. For the first time, we find significant evolution (>3σ) of the Mtot-T relation, pointing to an increase of the kinetic- to-thermal energy ratio with redshift. This is consistent with a scenario in which higher-redshift clusters are on average more disturbed than their lower-redshift counterparts.
RELICS: spectroscopy of gravitationally lensed z ? 2 reionization-era analogues and implications for C III] detections at z > 6Mainali, RameshStark, Daniel P.Tang, MengtaoChevallard, JacopoCharlot, StéphaneSharon, KerenCoe, DanSalmon, BrettBradley, Larry D.Johnson, Traci L.Frye, BrendaAvila, Roberto J.Ogaz, SaraZitrin, AdiBradac, MarušaLemaux, Brian C.Mahler, GuillaumePaterno-Mahler, RachelStrait, VictoriaAndrade-Santos, FelipeDOI: info:10.1093/mnras/staa751v. 494719–735
Mainali, Ramesh, Stark, Daniel P., Tang, Mengtao, Chevallard, Jacopo, Charlot, Stéphane, Sharon, Keren, Coe, Dan, Salmon, Brett, Bradley, Larry D., Johnson, Traci L., Frye, Brenda, Avila, Roberto J., Ogaz, Sara, Zitrin, Adi, Bradac, Maruša, Lemaux, Brian C., Mahler, Guillaume, Paterno-Mahler, Rachel, Strait, Victoria, and Andrade-Santos, Felipe. 2020. "RELICS: spectroscopy of gravitationally lensed z ? 2 reionization-era analogues and implications for C III] detections at z > 6." Monthly Notices of the Royal Astronomical Society 494:719– 735. https://doi.org/10.1093/mnras/staa751
ID: 158759
Type: article
Authors: Mainali, Ramesh; Stark, Daniel P.; Tang, Mengtao; Chevallard, Jacopo; Charlot, Stéphane; Sharon, Keren; Coe, Dan; Salmon, Brett; Bradley, Larry D.; Johnson, Traci L.; Frye, Brenda; Avila, Roberto J.; Ogaz, Sara; Zitrin, Adi; Bradac, Maruša; Lemaux, Brian C.; Mahler, Guillaume; Paterno-Mahler, Rachel; Strait, Victoria; Andrade-Santos, Felipe
Abstract: Recent observations have revealed the presence of strong C III] emission (EWC III > 20 Å) in z > 6 galaxies, the origin of which remains unclear. In an effort to understand the nature of these line emitters, we have initiated a survey targeting C III] emission in gravitationally lensed reionization-era analogues identified in Hubble Space Telescope imaging of clusters from the Reionization Lensing Cluster Survey. Here, we report initial results on four galaxies selected to have low stellar masses (2-8 × 107 M?) and J125-band flux excesses indicative of intense [O III] + H ß emission (EW[O III]+H ß = 500-2000 Å), similar to what has been observed at z > 6. We detect C III] emission in three of the four sources, with the C III] EW reaching values seen in the reionization era (EWC III]? 17-22 in the two sources with the strongest optical line emission (EW[O III]+H ß ? 2000 Å). We have obtained a Magellan/FIRE (Folded-port InfraRed Echellette) near-infrared spectrum of the strongest C III] emitter in our sample, revealing gas that is both metal poor and highly ionized. Using photoionization models, we are able to simultaneously reproduce the intense C III] and optical line emission for extremely young (2-3 Myr) and metal-poor (0.06-0.08 Z?) stellar populations, as would be expected after a substantial upturn in the star formation rate of a low-mass galaxy. The sources in this survey are among the first for which C III] has been used as the primary means of redshift confirmation. We suggest that it should be possible to extend this approach to z > 6 with current facilities, using C III] to measure redshifts of objects with IRAC excesses indicating EW[O III]+Hß ? 2000 Å, providing a method of spectroscopic confirmation independent of Ly a.
Type: article
Authors: Mainali, Ramesh; Stark, Daniel P.; Tang, Mengtao; Chevallard, Jacopo; Charlot, Stéphane; Sharon, Keren; Coe, Dan; Salmon, Brett; Bradley, Larry D.; Johnson, Traci L.; Frye, Brenda; Avila, Roberto J.; Ogaz, Sara; Zitrin, Adi; Bradac, Maruša; Lemaux, Brian C.; Mahler, Guillaume; Paterno-Mahler, Rachel; Strait, Victoria; Andrade-Santos, Felipe
Abstract: Recent observations have revealed the presence of strong C III] emission (EWC III > 20 Å) in z > 6 galaxies, the origin of which remains unclear. In an effort to understand the nature of these line emitters, we have initiated a survey targeting C III] emission in gravitationally lensed reionization-era analogues identified in Hubble Space Telescope imaging of clusters from the Reionization Lensing Cluster Survey. Here, we report initial results on four galaxies selected to have low stellar masses (2-8 × 107 M?) and J125-band flux excesses indicative of intense [O III] + H ß emission (EW[O III]+H ß = 500-2000 Å), similar to what has been observed at z > 6. We detect C III] emission in three of the four sources, with the C III] EW reaching values seen in the reionization era (EWC III]? 17-22 in the two sources with the strongest optical line emission (EW[O III]+H ß ? 2000 Å). We have obtained a Magellan/FIRE (Folded-port InfraRed Echellette) near-infrared spectrum of the strongest C III] emitter in our sample, revealing gas that is both metal poor and highly ionized. Using photoionization models, we are able to simultaneously reproduce the intense C III] and optical line emission for extremely young (2-3 Myr) and metal-poor (0.06-0.08 Z?) stellar populations, as would be expected after a substantial upturn in the star formation rate of a low-mass galaxy. The sources in this survey are among the first for which C III] has been used as the primary means of redshift confirmation. We suggest that it should be possible to extend this approach to z > 6 with current facilities, using C III] to measure redshifts of objects with IRAC excesses indicating EW[O III]+Hß ? 2000 Å, providing a method of spectroscopic confirmation independent of Ly a.
RELICS: The Reionization Lensing Cluster Survey and the Brightest High-z GalaxiesSalmon, BrettCoe, DanBradley, LarryBouwens, RychardBradač, MarusaHuang, Kuang-HanOesch, Pascal A.Stark, DanielSharon, KerenTrenti, MicheleAvila, Roberto J.Ogaz, SaraAndrade-Santos, FelipeCarrasco, DanielaCerny, CatherineDawson, WilliamFrye, Brenda L.Hoag, AustinJohnson, Traci LinJones, ChristineLam, DanielLovisari, LorenzoMainali, RameshPast, MattPaterno-Mahler, RachelPeterson, AveryRiess, Adam G.Rodney, Steven A.Ryan, Russel E.Sendra-Server, IreneStrait, VictoriaStrolger, Louis-GregoryUmetsu, KeiichiVulcani, BenedettaZitrin, AdiDOI: info:10.3847/1538-4357/ab5a8bv. 889189
Salmon, Brett, Coe, Dan, Bradley, Larry, Bouwens, Rychard, Bradač, Marusa, Huang, Kuang-Han, Oesch, Pascal A., Stark, Daniel, Sharon, Keren, Trenti, Michele, Avila, Roberto J., Ogaz, Sara, Andrade-Santos, Felipe, Carrasco, Daniela, Cerny, Catherine, Dawson, William, Frye, Brenda L., Hoag, Austin, Johnson, Traci Lin, Jones, Christine, Lam, Daniel, Lovisari, Lorenzo, Mainali, Ramesh, Past, Matt, Paterno-Mahler, Rachel et al. 2020. "RELICS: The Reionization Lensing Cluster Survey and the Brightest High-z Galaxies." The Astrophysical Journal 889:189. https://doi.org/10.3847/1538-4357/ab5a8b
ID: 156218
Type: article
Authors: Salmon, Brett; Coe, Dan; Bradley, Larry; Bouwens, Rychard; Bradač, Marusa; Huang, Kuang-Han; Oesch, Pascal A.; Stark, Daniel; Sharon, Keren; Trenti, Michele; Avila, Roberto J.; Ogaz, Sara; Andrade-Santos, Felipe; Carrasco, Daniela; Cerny, Catherine; Dawson, William; Frye, Brenda L.; Hoag, Austin; Johnson, Traci Lin; Jones, Christine; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Past, Matt; Paterno-Mahler, Rachel; Peterson, Avery; Riess, Adam G.; Rodney, Steven A.; Ryan, Russel E.; Sendra-Server, Irene; Strait, Victoria; Strolger, Louis-Gregory; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a view into both the extremely distant and intrinsically faint galaxy populations. We present here the $z\sim 6\mbox{--}8$ candidate high-redshift galaxies from the Reionization Lensing Cluster Survey (RELICS), a Hubble and Spitzer Space Telescope survey of 41 massive galaxy clusters spanning an area of ≈200 arcmin2. These clusters were selected to be excellent lenses, and we find similar high-redshift sample sizes and magnitude distributions as the Cluster Lensing And Supernova survey with Hubble (CLASH). We discover 257, 57, and eight candidate galaxies at z ∼ 6, 7, and 8 respectively, (322 in total). The observed (lensed) magnitudes of the z ∼ 6 candidates are as bright as AB mag ∼23, making them among the brightest known at these redshifts, comparable with discoveries from much wider, blank-field surveys. RELICS demonstrates the efficiency of using strong gravitational lenses to produce high-redshift samples in the epoch of reionization. These brightly observed galaxies are excellent targets for follow-up study with current and future observatories, including the James Webb Space Telescope.
Type: article
Authors: Salmon, Brett; Coe, Dan; Bradley, Larry; Bouwens, Rychard; Bradač, Marusa; Huang, Kuang-Han; Oesch, Pascal A.; Stark, Daniel; Sharon, Keren; Trenti, Michele; Avila, Roberto J.; Ogaz, Sara; Andrade-Santos, Felipe; Carrasco, Daniela; Cerny, Catherine; Dawson, William; Frye, Brenda L.; Hoag, Austin; Johnson, Traci Lin; Jones, Christine; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Past, Matt; Paterno-Mahler, Rachel; Peterson, Avery; Riess, Adam G.; Rodney, Steven A.; Ryan, Russel E.; Sendra-Server, Irene; Strait, Victoria; Strolger, Louis-Gregory; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a view into both the extremely distant and intrinsically faint galaxy populations. We present here the $z\sim 6\mbox{--}8$ candidate high-redshift galaxies from the Reionization Lensing Cluster Survey (RELICS), a Hubble and Spitzer Space Telescope survey of 41 massive galaxy clusters spanning an area of ≈200 arcmin2. These clusters were selected to be excellent lenses, and we find similar high-redshift sample sizes and magnitude distributions as the Cluster Lensing And Supernova survey with Hubble (CLASH). We discover 257, 57, and eight candidate galaxies at z ∼ 6, 7, and 8 respectively, (322 in total). The observed (lensed) magnitudes of the z ∼ 6 candidates are as bright as AB mag ∼23, making them among the brightest known at these redshifts, comparable with discoveries from much wider, blank-field surveys. RELICS demonstrates the efficiency of using strong gravitational lenses to produce high-redshift samples in the epoch of reionization. These brightly observed galaxies are excellent targets for follow-up study with current and future observatories, including the James Webb Space Telescope.
The discovery of radio halos in the frontier fields clusters Abell S1063 and Abell 370Xie, C.van Weeren, Reinout J.Lovisari, L.Andrade-Santos, FelipeBotteon, A.Brüggen, M.Bulbul, EsraChurazov, E.Clarke, T. E.Forman, William R.Intema, H. T.Jones, C.Kraft, Ralph P.Lal, D. V.Mroczkowski, T.Zitrin, A.DOI: info:10.1051/0004-6361/201936953v. 636A3
Xie, C., van Weeren, Reinout J., Lovisari, L., Andrade-Santos, Felipe, Botteon, A., Brüggen, M., Bulbul, Esra, Churazov, E., Clarke, T. E., Forman, William R., Intema, H. T., Jones, C., Kraft, Ralph P., Lal, D. V., Mroczkowski, T., and Zitrin, A. 2020. "The discovery of radio halos in the frontier fields clusters Abell S1063 and Abell 370." Astronomy and Astrophysics 636:A3. https://doi.org/10.1051/0004-6361/201936953
ID: 156987
Type: article
Authors: Xie, C.; van Weeren, Reinout J.; Lovisari, L.; Andrade-Santos, Felipe; Botteon, A.; Brüggen, M.; Bulbul, Esra; Churazov, E.; Clarke, T. E.; Forman, William R.; Intema, H. T.; Jones, C.; Kraft, Ralph P.; Lal, D. V.; Mroczkowski, T.; Zitrin, A.
Abstract: Context. Massive merging galaxy clusters often host diffuse megaparsec- scale radio synchrotron emission. This emission originates from relativistic electrons in the ionized intracluster medium. An important question is how these synchrotron emitting relativistic electrons are accelerated.
Aims: Our aim is to search for diffuse emission in the Frontier Fields clusters Abell S1063 and Abell 370 and characterize its properties. While these clusters are very massive and well studied at some other wavelengths, no diffuse emission has been reported for these clusters so far.
Methods: We obtained 325 MHz Giant Metrewave Radio Telescope (GMRT) and 1-4 GHz Jansky Very Large Array (VLA) observations of Abell S1063 and Abell 370. We complement these data with Chandra and XMM-Newton X-ray observations.
Results: In our sensitive images, we discover radio halos in both clusters. In Abell S1063, a giant radio halo is found with a size of ∼1.2 Mpc. The integrated spectral index between 325 MHz and 1.5 GHz is -0.94 ± 0.08 and it steepens to -1.77 ± 0.20 between 1.5 and 3.0 GHz. This spectral steepening provides support for the turbulent reacceleration model for radio halo formation. Abell 370 hosts a faint radio halo mostly centered on the southern part of this binary merging cluster, with a size of ∼500-700 kpc. The spectral index between 325 MHz and 1.5 GHz is -1.10 ± 0.09. Both radio halos follow the known scaling relation between the cluster mass proxy Y500 and radio power, which is consistent with the idea that they are related to ongoing cluster merger events.
Type: article
Authors: Xie, C.; van Weeren, Reinout J.; Lovisari, L.; Andrade-Santos, Felipe; Botteon, A.; Brüggen, M.; Bulbul, Esra; Churazov, E.; Clarke, T. E.; Forman, William R.; Intema, H. T.; Jones, C.; Kraft, Ralph P.; Lal, D. V.; Mroczkowski, T.; Zitrin, A.
Abstract: Context. Massive merging galaxy clusters often host diffuse megaparsec- scale radio synchrotron emission. This emission originates from relativistic electrons in the ionized intracluster medium. An important question is how these synchrotron emitting relativistic electrons are accelerated.
Aims: Our aim is to search for diffuse emission in the Frontier Fields clusters Abell S1063 and Abell 370 and characterize its properties. While these clusters are very massive and well studied at some other wavelengths, no diffuse emission has been reported for these clusters so far.
Methods: We obtained 325 MHz Giant Metrewave Radio Telescope (GMRT) and 1-4 GHz Jansky Very Large Array (VLA) observations of Abell S1063 and Abell 370. We complement these data with Chandra and XMM-Newton X-ray observations.
Results: In our sensitive images, we discover radio halos in both clusters. In Abell S1063, a giant radio halo is found with a size of ∼1.2 Mpc. The integrated spectral index between 325 MHz and 1.5 GHz is -0.94 ± 0.08 and it steepens to -1.77 ± 0.20 between 1.5 and 3.0 GHz. This spectral steepening provides support for the turbulent reacceleration model for radio halo formation. Abell 370 hosts a faint radio halo mostly centered on the southern part of this binary merging cluster, with a size of ∼500-700 kpc. The spectral index between 325 MHz and 1.5 GHz is -1.10 ± 0.09. Both radio halos follow the known scaling relation between the cluster mass proxy Y500 and radio power, which is consistent with the idea that they are related to ongoing cluster merger events.
RELICS: High-resolution Constraints on the Inner Mass Distribution of the z = 0.83 Merging Cluster RXJ0152.7-1357 from Strong LensingAcebron, AnaAlon, MayZitrin, AdiMahler, GuillaumeCoe, DanSharon, KerenCibirka, NatháliaBradač, MarušaTrenti, MicheleUmetsu, KeiichiAndrade-Santos, FelipeAvila, Roberto J.Bradley, LarryCarrasco, DanielaCerny, CatherineCzakon, Nicole G.Dawson, William A.Frye, BrendaHoag, Austin T.Huang, Kuang-HanJohnson, Traci L.Jones, ChristineKikuchihara, ShotaroLam, DanielLivermore, Rachael C.Lovisari, LorenzoMainali, RameshOesch, Pascal A.Ogaz, SaraOuchi, MasamiPast, MatthewPaterno-Mahler, RachelPeterson, AveryRyan, Russell E.Salmon, BrettSendra-Server, IreneStark, Daniel P.Strait, VictoriaToft, SuneVulcani, BenedettaDOI: info:10.3847/1538-4357/ab0adfv. 874132
Acebron, Ana, Alon, May, Zitrin, Adi, Mahler, Guillaume, Coe, Dan, Sharon, Keren, Cibirka, Nathália, Bradač, Maruša, Trenti, Michele, Umetsu, Keiichi, Andrade-Santos, Felipe, Avila, Roberto J., Bradley, Larry, Carrasco, Daniela, Cerny, Catherine, Czakon, Nicole G., Dawson, William A., Frye, Brenda, Hoag, Austin T., Huang, Kuang-Han, Johnson, Traci L., Jones, Christine, Kikuchihara, Shotaro, Lam, Daniel, Livermore, Rachael C. et al. 2019. "RELICS: High-resolution Constraints on the Inner Mass Distribution of the z = 0.83 Merging Cluster RXJ0152.7-1357 from Strong Lensing." The Astrophysical Journal 874:132. https://doi.org/10.3847/1538-4357/ab0adf
ID: 155247
Type: article
Authors: Acebron, Ana; Alon, May; Zitrin, Adi; Mahler, Guillaume; Coe, Dan; Sharon, Keren; Cibirka, Nathália; Bradač, Maruša; Trenti, Michele; Umetsu, Keiichi; Andrade-Santos, Felipe; Avila, Roberto J.; Bradley, Larry; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Livermore, Rachael C.; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Strait, Victoria; Toft, Sune; Vulcani, Benedetta
Abstract: Strong gravitational lensing (SL) is a powerful means of mapping the distribution of dark matter. In this work, we perform an SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (z = 0.83, also known as CL0152.7-1357) in Hubble Space Telescope images, taken in the framework of the Reionization Lensing Cluster Survey (RELICS). On top of a previously known z = 3.93 galaxy multiply imaged by RXJ0152.7-1357, for which we identify an additional multiple image, guided by a light- traces-mass approach, we identify seven new sets of multiply imaged background sources lensed by this cluster, spanning the redshift range [1.79-3.93]. A total of 25 multiple images are seen over a small area of ∼0.4 arcmin2, allowing us to put relatively high-resolution constraints on the inner matter distribution. Although modestly massive, the high degree of substructure, together with its very elongated shape, makes RXJ0152.7-1357 a very efficient lens for its size. This cluster also comprises the third-largest sample of z ∼ 6-7 candidates in the RELICS survey. Finally, we present a comparison of our resulting mass distribution and magnification estimates with those from a Lenstool model. These models are made publicly available through the Mikulski Archive for Space Telescopes.
Type: article
Authors: Acebron, Ana; Alon, May; Zitrin, Adi; Mahler, Guillaume; Coe, Dan; Sharon, Keren; Cibirka, Nathália; Bradač, Maruša; Trenti, Michele; Umetsu, Keiichi; Andrade-Santos, Felipe; Avila, Roberto J.; Bradley, Larry; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Livermore, Rachael C.; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Strait, Victoria; Toft, Sune; Vulcani, Benedetta
Abstract: Strong gravitational lensing (SL) is a powerful means of mapping the distribution of dark matter. In this work, we perform an SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (z = 0.83, also known as CL0152.7-1357) in Hubble Space Telescope images, taken in the framework of the Reionization Lensing Cluster Survey (RELICS). On top of a previously known z = 3.93 galaxy multiply imaged by RXJ0152.7-1357, for which we identify an additional multiple image, guided by a light- traces-mass approach, we identify seven new sets of multiply imaged background sources lensed by this cluster, spanning the redshift range [1.79-3.93]. A total of 25 multiple images are seen over a small area of ∼0.4 arcmin2, allowing us to put relatively high-resolution constraints on the inner matter distribution. Although modestly massive, the high degree of substructure, together with its very elongated shape, makes RXJ0152.7-1357 a very efficient lens for its size. This cluster also comprises the third-largest sample of z ∼ 6-7 candidates in the RELICS survey. Finally, we present a comparison of our resulting mass distribution and magnification estimates with those from a Lenstool model. These models are made publicly available through the Mikulski Archive for Space Telescopes.
Chandra Observations of the Spectacular A3411─12 Merger EventAndrade-Santos, Felipevan Weeren, Reinout J.Di Gennaro, GabriellaWittman, DavidRyu, DongsuVir Lal, DharamPlacco, Vinicius M.Fogarty, KevinJee, M. JamesStroe, AndraSobral, DavidForman, William R.Jones, ChristineKraft, Ralph P.Murray, Stephen S.Brüggen, MarcusKang, HyesungSantucci, RafaelGolovich, NathanDawson, WilliamDOI: info:10.3847/1538-4357/ab4ce5v. 88731
Andrade-Santos, Felipe, van Weeren, Reinout J., Di Gennaro, Gabriella, Wittman, David, Ryu, Dongsu, Vir Lal, Dharam, Placco, Vinicius M., Fogarty, Kevin, Jee, M. James, Stroe, Andra, Sobral, David, Forman, William R., Jones, Christine, Kraft, Ralph P., Murray, Stephen S., Brüggen, Marcus, Kang, Hyesung, Santucci, Rafael, Golovich, Nathan, and Dawson, William. 2019. "Chandra Observations of the Spectacular A3411─12 Merger Event." The Astrophysical Journal 887:31. https://doi.org/10.3847/1538-4357/ab4ce5
ID: 154553
Type: article
Authors: Andrade-Santos, Felipe; van Weeren, Reinout J.; Di Gennaro, Gabriella; Wittman, David; Ryu, Dongsu; Vir Lal, Dharam; Placco, Vinicius M.; Fogarty, Kevin; Jee, M. James; Stroe, Andra; Sobral, David; Forman, William R.; Jones, Christine; Kraft, Ralph P.; Murray, Stephen S.; Brüggen, Marcus; Kang, Hyesung; Santucci, Rafael; Golovich, Nathan; Dawson, William
Abstract: We present deep Chandra observations of A3411─12, a remarkable merging cluster that hosts the most compelling evidence for electron reacceleration at cluster shocks to date. Using the {Y}{{X}}{--}M scaling relation, we find r 500 ∼ 1.3 Mpc, {M}500=(7.1+/- 0.7)× {10}14 {M}ȯ , {kT}=6.5+/- 0.1 {keV}, and a gas mass of {M}{{g},500}=(9.7+/- 0.1)× {10}13{M}ȯ . The gas mass fraction within r 500 is {f}{{g}}=0.14+/- 0.01. We compute the shock strength using density jumps to conclude that the Mach number of the merging subcluster is small (M≤slant {1.15}-0.09+0.14). We also present density, temperature, pseudo-pressure, and pseudo-entropy maps. Based on the pseudo-entropy map, we conclude that the cluster is undergoing a mild merger, consistent with the small Mach number. On the other hand, radio relics extend over Mpc scale in the A3411─12 system, which strongly suggests that a population of energetic electrons already existed over extended regions of the cluster.
Type: article
Authors: Andrade-Santos, Felipe; van Weeren, Reinout J.; Di Gennaro, Gabriella; Wittman, David; Ryu, Dongsu; Vir Lal, Dharam; Placco, Vinicius M.; Fogarty, Kevin; Jee, M. James; Stroe, Andra; Sobral, David; Forman, William R.; Jones, Christine; Kraft, Ralph P.; Murray, Stephen S.; Brüggen, Marcus; Kang, Hyesung; Santucci, Rafael; Golovich, Nathan; Dawson, William
Abstract: We present deep Chandra observations of A3411─12, a remarkable merging cluster that hosts the most compelling evidence for electron reacceleration at cluster shocks to date. Using the {Y}{{X}}{--}M scaling relation, we find r 500 ∼ 1.3 Mpc, {M}500=(7.1+/- 0.7)× {10}14 {M}ȯ , {kT}=6.5+/- 0.1 {keV}, and a gas mass of {M}{{g},500}=(9.7+/- 0.1)× {10}13{M}ȯ . The gas mass fraction within r 500 is {f}{{g}}=0.14+/- 0.01. We compute the shock strength using density jumps to conclude that the Mach number of the merging subcluster is small (M≤slant {1.15}-0.09+0.14). We also present density, temperature, pseudo-pressure, and pseudo-entropy maps. Based on the pseudo-entropy map, we conclude that the cluster is undergoing a mild merger, consistent with the small Mach number. On the other hand, radio relics extend over Mpc scale in the A3411─12 system, which strongly suggests that a population of energetic electrons already existed over extended regions of the cluster.
RELICS: Reionization Lensing Cluster SurveyCoe, DanSalmon, BrettBradač, MarušaBradley, Larry D.Sharon, KerenZitrin, AdiAcebron, AnaCerny, CatherineCibirka, NatháliaStrait, VictoriaPaterno-Mahler, RachelMahler, GuillaumeAvila, Roberto J.Ogaz, SaraHuang, Kuang-HanPelliccia, DeboraStark, Daniel P.Mainali, RameshOesch, Pascal A.Trenti, MicheleCarrasco, DanielaDawson, William A.Rodney, Steven A.Strolger, Louis-GregoryRiess, Adam G.Jones, ChristineFrye, Brenda L.Czakon, Nicole G.Umetsu, KeiichiVulcani, BenedettaGraur, OrJha, Saurabh W.Graham, Melissa L.Molino, AlbertoNonino, MarioHjorth, JensSelsing, JonatanChristensen, LiseKikuchihara, ShotaroOuchi, MasamiOguri, MasamuneWelch, BrianLemaux, Brian C.Andrade-Santos, FelipeHoag, Austin T.Johnson, Traci L.Peterson, AveryPast, MatthewFox, CarterAgulli, IreneLivermore, RachaelRyan, Russell E.Lam, DanielSendra-Server, IreneToft, SuneLovisari, LorenzoSu, YuanyuanDOI: info:10.3847/1538-4357/ab412bv. 88485
Coe, Dan, Salmon, Brett, Bradač, Maruša, Bradley, Larry D., Sharon, Keren, Zitrin, Adi, Acebron, Ana, Cerny, Catherine, Cibirka, Nathália, Strait, Victoria, Paterno-Mahler, Rachel, Mahler, Guillaume, Avila, Roberto J., Ogaz, Sara, Huang, Kuang-Han, Pelliccia, Debora, Stark, Daniel P., Mainali, Ramesh, Oesch, Pascal A., Trenti, Michele, Carrasco, Daniela, Dawson, William A., Rodney, Steven A., Strolger, Louis-Gregory, Riess, Adam G. et al. 2019. "RELICS: Reionization Lensing Cluster Survey." The Astrophysical Journal 884:85. https://doi.org/10.3847/1538-4357/ab412b
ID: 154720
Type: article
Authors: Coe, Dan; Salmon, Brett; Bradač, Maruša; Bradley, Larry D.; Sharon, Keren; Zitrin, Adi; Acebron, Ana; Cerny, Catherine; Cibirka, Nathália; Strait, Victoria; Paterno-Mahler, Rachel; Mahler, Guillaume; Avila, Roberto J.; Ogaz, Sara; Huang, Kuang-Han; Pelliccia, Debora; Stark, Daniel P.; Mainali, Ramesh; Oesch, Pascal A.; Trenti, Michele; Carrasco, Daniela; Dawson, William A.; Rodney, Steven A.; Strolger, Louis-Gregory; Riess, Adam G.; Jones, Christine; Frye, Brenda L.; Czakon, Nicole G.; Umetsu, Keiichi; Vulcani, Benedetta; Graur, Or; Jha, Saurabh W.; Graham, Melissa L.; Molino, Alberto; Nonino, Mario; Hjorth, Jens; Selsing, Jonatan; Christensen, Lise; Kikuchihara, Shotaro; Ouchi, Masami; Oguri, Masamune; Welch, Brian; Lemaux, Brian C.; Andrade-Santos, Felipe; Hoag, Austin T.; Johnson, Traci L.; Peterson, Avery; Past, Matthew; Fox, Carter; Agulli, Irene; Livermore, Rachael; Ryan, Russell E.; Lam, Daniel; Sendra-Server, Irene; Toft, Sune; Lovisari, Lorenzo; Su, Yuanyuan
Abstract: Large surveys of galaxy clusters with the Hubble Space Telescope (HST) and Spitzer, including the Cluster Lensing And Supernova survey with Hubble and the Frontier Fields, have demonstrated the power of strong gravitational lensing to efficiently deliver large samples of high- redshift galaxies. We extend this strategy through a wider, shallower survey named RELICS, the Reionization Lensing Cluster Survey, described here. Our 188-orbit Hubble Treasury Program observed 41 clusters at 0.182 ≤ z ≤ 0.972 with Advanced Camera for Surveys (ACS) and WFC3/IR imaging spanning 0.4-1.7 μm. We selected 21 of the most massive clusters known based on Planck PSZ2 estimates and 20 additional clusters based on observed or inferred lensing strength. RELICS observed 46 WFC3/IR pointings (̃200 arcmin2) each with two orbits divided among four filters (F105W, F125W, F140W, and F160W) and ACS imaging as needed to achieve single-orbit depth in each of three filters (F435W, F606W, and F814W). As previously reported by Salmon et al., we discovered over 300 z ̃ 6-10 candidates, including the brightest z ̃ 6 candidates known, and the most distant spatially resolved lensed arc known at z ̃ 10. Spitzer IRAC imaging (945 hr awarded, plus 100 archival, spanning 3.0-5.0 μm) has crucially enabled us to distinguish z ̃ 10 candidates from z ̃ 2 interlopers. For each cluster, two HST observing epochs were staggered by about a month, enabling us to discover 11 supernovae, including 3 lensed supernovae, which we followed up with 20 orbits from our program. Reduced HST images, catalogs, and lens models are available on MAST, and reduced Spitzer images are available on IRSA.
Type: article
Authors: Coe, Dan; Salmon, Brett; Bradač, Maruša; Bradley, Larry D.; Sharon, Keren; Zitrin, Adi; Acebron, Ana; Cerny, Catherine; Cibirka, Nathália; Strait, Victoria; Paterno-Mahler, Rachel; Mahler, Guillaume; Avila, Roberto J.; Ogaz, Sara; Huang, Kuang-Han; Pelliccia, Debora; Stark, Daniel P.; Mainali, Ramesh; Oesch, Pascal A.; Trenti, Michele; Carrasco, Daniela; Dawson, William A.; Rodney, Steven A.; Strolger, Louis-Gregory; Riess, Adam G.; Jones, Christine; Frye, Brenda L.; Czakon, Nicole G.; Umetsu, Keiichi; Vulcani, Benedetta; Graur, Or; Jha, Saurabh W.; Graham, Melissa L.; Molino, Alberto; Nonino, Mario; Hjorth, Jens; Selsing, Jonatan; Christensen, Lise; Kikuchihara, Shotaro; Ouchi, Masami; Oguri, Masamune; Welch, Brian; Lemaux, Brian C.; Andrade-Santos, Felipe; Hoag, Austin T.; Johnson, Traci L.; Peterson, Avery; Past, Matthew; Fox, Carter; Agulli, Irene; Livermore, Rachael; Ryan, Russell E.; Lam, Daniel; Sendra-Server, Irene; Toft, Sune; Lovisari, Lorenzo; Su, Yuanyuan
Abstract: Large surveys of galaxy clusters with the Hubble Space Telescope (HST) and Spitzer, including the Cluster Lensing And Supernova survey with Hubble and the Frontier Fields, have demonstrated the power of strong gravitational lensing to efficiently deliver large samples of high- redshift galaxies. We extend this strategy through a wider, shallower survey named RELICS, the Reionization Lensing Cluster Survey, described here. Our 188-orbit Hubble Treasury Program observed 41 clusters at 0.182 ≤ z ≤ 0.972 with Advanced Camera for Surveys (ACS) and WFC3/IR imaging spanning 0.4-1.7 μm. We selected 21 of the most massive clusters known based on Planck PSZ2 estimates and 20 additional clusters based on observed or inferred lensing strength. RELICS observed 46 WFC3/IR pointings (̃200 arcmin2) each with two orbits divided among four filters (F105W, F125W, F140W, and F160W) and ACS imaging as needed to achieve single-orbit depth in each of three filters (F435W, F606W, and F814W). As previously reported by Salmon et al., we discovered over 300 z ̃ 6-10 candidates, including the brightest z ̃ 6 candidates known, and the most distant spatially resolved lensed arc known at z ̃ 10. Spitzer IRAC imaging (945 hr awarded, plus 100 archival, spanning 3.0-5.0 μm) has crucially enabled us to distinguish z ̃ 10 candidates from z ̃ 2 interlopers. For each cluster, two HST observing epochs were staggered by about a month, enabling us to discover 11 supernovae, including 3 lensed supernovae, which we followed up with 20 orbits from our program. Reduced HST images, catalogs, and lens models are available on MAST, and reduced Spitzer images are available on IRSA.
Evidence for a Merger-induced Shock Wave in ZwCl 0008.8+5215 with Chandra and SuzakuDi Gennaro, Gabriellavan Weeren, Reinout J.Andrade-Santos, FelipeAkamatsu, H.Randall, Scott W.Forman, William R.Kraft, Ralph P.Brunetti, G.Dawson, W. A.Golovich, N.Jones, ChristineDOI: info:10.3847/1538-4357/ab03cdv. 87364
Di Gennaro, Gabriella, van Weeren, Reinout J., Andrade-Santos, Felipe, Akamatsu, H., Randall, Scott W., Forman, William R., Kraft, Ralph P., Brunetti, G., Dawson, W. A., Golovich, N., and Jones, Christine. 2019. "Evidence for a Merger-induced Shock Wave in ZwCl 0008.8+5215 with Chandra and Suzaku." The Astrophysical Journal 873:64. https://doi.org/10.3847/1538-4357/ab03cd
ID: 150904
Type: article
Authors: Di Gennaro, Gabriella; van Weeren, Reinout J.; Andrade-Santos, Felipe; Akamatsu, H.; Randall, Scott W.; Forman, William R.; Kraft, Ralph P.; Brunetti, G.; Dawson, W. A.; Golovich, N.; Jones, Christine
Abstract: We present the results from new deep Chandra (∼410 ks) and Suzaku (∼180 ks) observations of the merging galaxy cluster ZwCl 0008.8+5215 (z = 0.104). Previous radio observations revealed the presence of a double radio relic located diametrically west and east of the cluster center. Using our new Chandra data, we find evidence for the presence of a shock at the location of the western relic, RW, with a Mach number {{ \mathcal M }}{SX}={1.48}-0.32+0.50 from the density jump. We also measure {{ \mathcal M }}{TX}={2.35}-0.55+0.74 and {{ \mathcal M }}{TX}={2.02}-0.47+0.74 from the temperature jump, with Chandra and Suzaku, respectively. These values are consistent with the Mach number estimate from a previous study of the radio spectral index, under the assumption of diffusive shock acceleration ({{ \mathcal M }}RW}={2.4}-0.2+0.4). Interestingly, the western radio relic does not entirely trace the X-ray shock. A possible explanation is that the relic traces fossil plasma from nearby radio galaxies that is reaccelerated at the shock. For the eastern relic we do not detect an X-ray surface brightness discontinuity, despite the fact that radio observations suggest a shock with {{ \mathcal M }}RE}={2.2}-0.1+0.2. The low surface brightness and reduced integration time for this region might have prevented the detection. The Chandra surface brightness profile suggests { \mathcal M }≲ 1.5, while the Suzaku temperature measurements found {{ \mathcal M }}{TX}={1.54}-0.47+0.65. Finally, we also detect a merger-induced cold front on the western side of the cluster, behind the shock that traces the western relic.
Type: article
Authors: Di Gennaro, Gabriella; van Weeren, Reinout J.; Andrade-Santos, Felipe; Akamatsu, H.; Randall, Scott W.; Forman, William R.; Kraft, Ralph P.; Brunetti, G.; Dawson, W. A.; Golovich, N.; Jones, Christine
Abstract: We present the results from new deep Chandra (∼410 ks) and Suzaku (∼180 ks) observations of the merging galaxy cluster ZwCl 0008.8+5215 (z = 0.104). Previous radio observations revealed the presence of a double radio relic located diametrically west and east of the cluster center. Using our new Chandra data, we find evidence for the presence of a shock at the location of the western relic, RW, with a Mach number {{ \mathcal M }}{SX}={1.48}-0.32+0.50 from the density jump. We also measure {{ \mathcal M }}{TX}={2.35}-0.55+0.74 and {{ \mathcal M }}{TX}={2.02}-0.47+0.74 from the temperature jump, with Chandra and Suzaku, respectively. These values are consistent with the Mach number estimate from a previous study of the radio spectral index, under the assumption of diffusive shock acceleration ({{ \mathcal M }}RW}={2.4}-0.2+0.4). Interestingly, the western radio relic does not entirely trace the X-ray shock. A possible explanation is that the relic traces fossil plasma from nearby radio galaxies that is reaccelerated at the shock. For the eastern relic we do not detect an X-ray surface brightness discontinuity, despite the fact that radio observations suggest a shock with {{ \mathcal M }}RE}={2.2}-0.1+0.2. The low surface brightness and reduced integration time for this region might have prevented the detection. The Chandra surface brightness profile suggests { \mathcal M }≲ 1.5, while the Suzaku temperature measurements found {{ \mathcal M }}{TX}={1.54}-0.47+0.65. Finally, we also detect a merger-induced cold front on the western side of the cluster, behind the shock that traces the western relic.
Radio observations of the merging galaxy cluster Abell 520Hoang, D. N.Shimwell, T. W.van Weeren, R. J.Brunetti, G.Röttgering, H. J. A.Andrade-Santos, FelipeBotteon, A.Brüggen, M.Cassano, R.Drabent, A.de Gasperin, F.Hoeft, M.Intema, H. T.Rafferty, D. A.Shweta, A.Stroe, A.DOI: info:10.1051/0004-6361/201833900v. 622A20
Hoang, D. N., Shimwell, T. W., van Weeren, R. J., Brunetti, G., Röttgering, H. J. A., Andrade-Santos, Felipe, Botteon, A., Brüggen, M., Cassano, R., Drabent, A., de Gasperin, F., Hoeft, M., Intema, H. T., Rafferty, D. A., Shweta, A., and Stroe, A. 2019. "Radio observations of the merging galaxy cluster Abell 520." Astronomy and Astrophysics 622:A20. https://doi.org/10.1051/0004-6361/201833900
ID: 155448
Type: article
Authors: Hoang, D. N.; Shimwell, T. W.; van Weeren, R. J.; Brunetti, G.; Röttgering, H. J. A.; Andrade-Santos, Felipe; Botteon, A.; Brüggen, M.; Cassano, R.; Drabent, A.; de Gasperin, F.; Hoeft, M.; Intema, H. T.; Rafferty, D. A.; Shweta, A.; Stroe, A.
Abstract: Context. Extended synchrotron radio sources are often observed in merging galaxy clusters. Studies of the extended emission help us to understand the mechanisms in which the radio emitting particles gain their relativistic energies. Aims: We examine the possible acceleration mechanisms of the relativistic particles that are responsible for the extended radio emission in the merging galaxy cluster Abell 520. Methods: We performed new 145 MHz observations with the LOw Frequency ARay (LOFAR) and combined these with archival Giant Metrewave Radio Telescope (GMRT) 323 MHz and Very Large Array (VLA) 1.5 GHz data to study the morphological and spectral properties of extended cluster emission. The observational properties are discussed in the framework of particle acceleration models associated with cluster merger turbulence and shocks. Results: In Abell 520, we confirm the presence of extended (760 × 950 kpc2) synchrotron radio emission that has been classified as a radio halo. The comparison between the radio and X-ray brightness suggests that the halo might originate in a cocoon rather than from the central X-ray bright regions of the cluster. The halo spectrum is roughly uniform on the scale of 66 kpc. There is a hint of spectral steepening from the SW edge towards the cluster centre. Assuming diffusive shock acceleration (DSA), the radio data are suggestive of a shock Mach number of ℳSW = 2.6-0.2+0.3 that is consistent with the X-ray derived estimates. This is in agreement with the scenario in which relativistic electrons in the SW radio edge gain their energies at the shock front via acceleration of either thermal or fossil electrons. We do not detect extended radio emission ahead of the SW shock that is predicted if the emission is the result of adiabatic compression. An X-ray surface brightness discontinuity is detected towards the NE region that may be a counter shock of Mach number ℳNEX = 1.52±0.05. This is lower than the value predicted from the radio emission which, assuming DSA, is consistent with ℳNE = 2.1 ± 0.2. Conclusions: Our observations indicate that the radio emission in the SW of Abell 520 is likely effected by the prominent X-ray detected shock in which radio emitting particles are (re-)accelerated through the Fermi-I mechanism. The NE X-ray discontinuity that is approximately collocated with an edge in the radio emission hints at the presence of a counter shock.
Type: article
Authors: Hoang, D. N.; Shimwell, T. W.; van Weeren, R. J.; Brunetti, G.; Röttgering, H. J. A.; Andrade-Santos, Felipe; Botteon, A.; Brüggen, M.; Cassano, R.; Drabent, A.; de Gasperin, F.; Hoeft, M.; Intema, H. T.; Rafferty, D. A.; Shweta, A.; Stroe, A.
Abstract: Context. Extended synchrotron radio sources are often observed in merging galaxy clusters. Studies of the extended emission help us to understand the mechanisms in which the radio emitting particles gain their relativistic energies. Aims: We examine the possible acceleration mechanisms of the relativistic particles that are responsible for the extended radio emission in the merging galaxy cluster Abell 520. Methods: We performed new 145 MHz observations with the LOw Frequency ARay (LOFAR) and combined these with archival Giant Metrewave Radio Telescope (GMRT) 323 MHz and Very Large Array (VLA) 1.5 GHz data to study the morphological and spectral properties of extended cluster emission. The observational properties are discussed in the framework of particle acceleration models associated with cluster merger turbulence and shocks. Results: In Abell 520, we confirm the presence of extended (760 × 950 kpc2) synchrotron radio emission that has been classified as a radio halo. The comparison between the radio and X-ray brightness suggests that the halo might originate in a cocoon rather than from the central X-ray bright regions of the cluster. The halo spectrum is roughly uniform on the scale of 66 kpc. There is a hint of spectral steepening from the SW edge towards the cluster centre. Assuming diffusive shock acceleration (DSA), the radio data are suggestive of a shock Mach number of ℳSW = 2.6-0.2+0.3 that is consistent with the X-ray derived estimates. This is in agreement with the scenario in which relativistic electrons in the SW radio edge gain their energies at the shock front via acceleration of either thermal or fossil electrons. We do not detect extended radio emission ahead of the SW shock that is predicted if the emission is the result of adiabatic compression. An X-ray surface brightness discontinuity is detected towards the NE region that may be a counter shock of Mach number ℳNEX = 1.52±0.05. This is lower than the value predicted from the radio emission which, assuming DSA, is consistent with ℳNE = 2.1 ± 0.2. Conclusions: Our observations indicate that the radio emission in the SW of Abell 520 is likely effected by the prominent X-ray detected shock in which radio emitting particles are (re-)accelerated through the Fermi-I mechanism. The NE X-ray discontinuity that is approximately collocated with an edge in the radio emission hints at the presence of a counter shock.
Radio observations of the merging galaxy cluster Abell 520 (Corrigendum)Hoang, D. N.Shimwell, T. W.van Weeren, R. J.Brunetti, G.Röttgering, Huub J. A.Andrade-Santos, F.Botteon, A.Brüggen, M.Cassano, R.Drabent, A.de Gasperin, F.Hoeft, M.Intema, H. T.Rafferty, D. A.Shweta, A.Stroe, A.DOI: info:10.1051/0004-6361/201833900ev. 624C1
Hoang, D. N., Shimwell, T. W., van Weeren, R. J., Brunetti, G., Röttgering, Huub J. A., Andrade-Santos, F., Botteon, A., Brüggen, M., Cassano, R., Drabent, A., de Gasperin, F., Hoeft, M., Intema, H. T., Rafferty, D. A., Shweta, A., and Stroe, A. 2019. "Radio observations of the merging galaxy cluster Abell 520 (Corrigendum)." Astronomy and Astrophysics 624:C1. https://doi.org/10.1051/0004-6361/201833900e
ID: 155160
Type: article
Authors: Hoang, D. N.; Shimwell, T. W.; van Weeren, R. J.; Brunetti, G.; Röttgering, Huub J. A.; Andrade-Santos, F.; Botteon, A.; Brüggen, M.; Cassano, R.; Drabent, A.; de Gasperin, F.; Hoeft, M.; Intema, H. T.; Rafferty, D. A.; Shweta, A.; Stroe, A.
Type: article
Authors: Hoang, D. N.; Shimwell, T. W.; van Weeren, R. J.; Brunetti, G.; Röttgering, Huub J. A.; Andrade-Santos, F.; Botteon, A.; Brüggen, M.; Cassano, R.; Drabent, A.; de Gasperin, F.; Hoeft, M.; Intema, H. T.; Rafferty, D. A.; Shweta, A.; Stroe, A.
RELICS: Strong Lensing Analysis of MACS J0417.5-1154 and Predictions for Observing the Magnified High-redshift Universe with JWSTMahler, GuillaumeSharon, KerenFox, CarterCoe, DanJauzac, MathildeStrait, VictoriaEdge, AlastairAcebron, AnaAndrade-Santos, FelipeAvila, Roberto J.Bradač, MarušaBradley, Larry D.Carrasco, DanielaCerny, CatherineCibirka, NatháliaCzakon, Nicole G.Dawson, William A.Frye, Brenda L.Hoag, Austin T.Huang, Kuang-HanJohnson, Traci L.Jones, ChristineKikuchihara, ShotaroLam, DanielLivermore, RachaelLovisari, LorenzoMainali, RameshOgaz, SaraOuchi, MasamiPaterno-Mahler, RachelRoederer, Ian U.Ryan, Russell E.Salmon, BrettSendra-Server, IreneStark, Daniel P.Toft, SuneTrenti, MicheleUmetsu, KeiichiVulcani, BenedettaZitrin, AdiDOI: info:10.3847/1538-4357/ab042bv. 87396
Mahler, Guillaume, Sharon, Keren, Fox, Carter, Coe, Dan, Jauzac, Mathilde, Strait, Victoria, Edge, Alastair, Acebron, Ana, Andrade-Santos, Felipe, Avila, Roberto J., Bradač, Maruša, Bradley, Larry D., Carrasco, Daniela, Cerny, Catherine, Cibirka, Nathália, Czakon, Nicole G., Dawson, William A., Frye, Brenda L., Hoag, Austin T., Huang, Kuang-Han, Johnson, Traci L., Jones, Christine, Kikuchihara, Shotaro, Lam, Daniel, Livermore, Rachael et al. 2019. "RELICS: Strong Lensing Analysis of MACS J0417.5-1154 and Predictions for Observing the Magnified High-redshift Universe with JWST." The Astrophysical Journal 873:96. https://doi.org/10.3847/1538-4357/ab042b
ID: 155415
Type: article
Authors: Mahler, Guillaume; Sharon, Keren; Fox, Carter; Coe, Dan; Jauzac, Mathilde; Strait, Victoria; Edge, Alastair; Acebron, Ana; Andrade-Santos, Felipe; Avila, Roberto J.; Bradač, Maruša; Bradley, Larry D.; Carrasco, Daniela; Cerny, Catherine; Cibirka, Nathália; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda L.; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Livermore, Rachael; Lovisari, Lorenzo; Mainali, Ramesh; Ogaz, Sara; Ouchi, Masami; Paterno-Mahler, Rachel; Roederer, Ian U.; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Toft, Sune; Trenti, Michele; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: Strong gravitational lensing by clusters of galaxies probes the mass distribution at the core of each cluster and magnifies the universe behind it. MACS J0417.5-1154 at z = 0.443 is one of the most massive clusters known based on weak lensing, X-ray, and Sunyaev-Zel'dovich analyses. Here we compute a strong lens model of MACS J0417 based on Hubble Space Telescope imaging observations collected, in part, by the Reionization Lensing Cluster Survey (RELICS), and recently reported spectroscopic redshifts from the MUSE instrument on the Very Large Telescope (VLT). We measure an Einstein radius of {θ }E≃ 36\prime\prime at z = 9 and a mass projected within 200 kpc of {M}(200{kpc)}={1.78}-0.03+0.01× {10}14 M {}☉ . Using this model, we measure a ratio between the mass attributed to cluster-member galaxy halos and the main cluster halo of order 1:100. We assess the probability to detect magnified high-redshift galaxies in the field of this cluster, both for comparison with RELICS HST results and as a prediction for the James Webb Space Telescope (JWST) Guaranteed Time Observations upcoming for this cluster. Our lensing analysis indicates that this cluster has similar lensing strength to other clusters in the RELICS program. Our lensing analysis predicts a detection of at least a few z ∼ 6-8 galaxies behind this cluster, at odds with a recent analysis that yielded no such candidates in this field. Reliable strong lensing models are crucial for accurately predicting the intrinsic properties of lensed galaxies. As part of the RELICS program, our strong lensing model produced with the Lenstool parametric method is publicly available through the Mikulski Archive for Space Telescopes.
Type: article
Authors: Mahler, Guillaume; Sharon, Keren; Fox, Carter; Coe, Dan; Jauzac, Mathilde; Strait, Victoria; Edge, Alastair; Acebron, Ana; Andrade-Santos, Felipe; Avila, Roberto J.; Bradač, Maruša; Bradley, Larry D.; Carrasco, Daniela; Cerny, Catherine; Cibirka, Nathália; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda L.; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Livermore, Rachael; Lovisari, Lorenzo; Mainali, Ramesh; Ogaz, Sara; Ouchi, Masami; Paterno-Mahler, Rachel; Roederer, Ian U.; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Toft, Sune; Trenti, Michele; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: Strong gravitational lensing by clusters of galaxies probes the mass distribution at the core of each cluster and magnifies the universe behind it. MACS J0417.5-1154 at z = 0.443 is one of the most massive clusters known based on weak lensing, X-ray, and Sunyaev-Zel'dovich analyses. Here we compute a strong lens model of MACS J0417 based on Hubble Space Telescope imaging observations collected, in part, by the Reionization Lensing Cluster Survey (RELICS), and recently reported spectroscopic redshifts from the MUSE instrument on the Very Large Telescope (VLT). We measure an Einstein radius of {θ }E≃ 36\prime\prime at z = 9 and a mass projected within 200 kpc of {M}(200{kpc)}={1.78}-0.03+0.01× {10}14 M {}☉ . Using this model, we measure a ratio between the mass attributed to cluster-member galaxy halos and the main cluster halo of order 1:100. We assess the probability to detect magnified high-redshift galaxies in the field of this cluster, both for comparison with RELICS HST results and as a prediction for the James Webb Space Telescope (JWST) Guaranteed Time Observations upcoming for this cluster. Our lensing analysis indicates that this cluster has similar lensing strength to other clusters in the RELICS program. Our lensing analysis predicts a detection of at least a few z ∼ 6-8 galaxies behind this cluster, at odds with a recent analysis that yielded no such candidates in this field. Reliable strong lensing models are crucial for accurately predicting the intrinsic properties of lensed galaxies. As part of the RELICS program, our strong lensing model produced with the Lenstool parametric method is publicly available through the Mikulski Archive for Space Telescopes.
Detection of a Star-forming Galaxy in the Center of a Low-mass Galaxy ClusterBogdán, ÁkosLovisari, LorenzoKovács, Orsolya E.Andrade-Santos, FelipeJones, ChristineForman, William R.Kraft, Ralph P.DOI: info:10.3847/1538-4357/aaee71v. 869105
Bogdán, Ákos, Lovisari, Lorenzo, Kovács, Orsolya E., Andrade-Santos, Felipe, Jones, Christine, Forman, William R., and Kraft, Ralph P. 2018. "Detection of a Star-forming Galaxy in the Center of a Low-mass Galaxy Cluster." The Astrophysical Journal 869:105. https://doi.org/10.3847/1538-4357/aaee71
ID: 150175
Type: article
Authors: Bogdán, Ákos; Lovisari, Lorenzo; Kovács, Orsolya E.; Andrade-Santos, Felipe; Jones, Christine; Forman, William R.; Kraft, Ralph P.
Abstract: Brightest Cluster Galaxies (BCGs) residing in the centers of galaxy clusters are typically quenched giant ellipticals. A recent study hinted that star-forming galaxies with large disks, so-called superluminous spirals and lenticulars, are the BCGs of a subset of galaxy clusters. Based on the existing optical data it was not possible to constrain whether the superluminous disk galaxies reside at the center of galaxy clusters. In this work, we utilize XMM-Newton X-ray observations of five galaxy clusters to map the morphology of the ICM, characterize the galaxy clusters, determine the position of the cluster center, and measure the offset between the cluster center and the superluminous disk galaxies. We demonstrate that one superluminous lenticular galaxy, 2MASX J10405643-0103584, resides at the center of a low-mass (M 500 = 1014 M ⊙) galaxy cluster. This represents the first conclusive evidence that a superluminous disk galaxy is the central BCG of a galaxy cluster. We speculate that the progenitor of 2MASX J10405643-0103584 was an elliptical galaxy, whose extended disk was re-formed due to the merger of galaxies. We exclude the possibility that the other four superluminous disk galaxies reside at the center of galaxy clusters, as their projected distance from the cluster center is 150–1070 kpc, which corresponds to (0.27–1.18)R 500. We conclude that these clusters host quiescent massive elliptical galaxies at their center.
Type: article
Authors: Bogdán, Ákos; Lovisari, Lorenzo; Kovács, Orsolya E.; Andrade-Santos, Felipe; Jones, Christine; Forman, William R.; Kraft, Ralph P.
Abstract: Brightest Cluster Galaxies (BCGs) residing in the centers of galaxy clusters are typically quenched giant ellipticals. A recent study hinted that star-forming galaxies with large disks, so-called superluminous spirals and lenticulars, are the BCGs of a subset of galaxy clusters. Based on the existing optical data it was not possible to constrain whether the superluminous disk galaxies reside at the center of galaxy clusters. In this work, we utilize XMM-Newton X-ray observations of five galaxy clusters to map the morphology of the ICM, characterize the galaxy clusters, determine the position of the cluster center, and measure the offset between the cluster center and the superluminous disk galaxies. We demonstrate that one superluminous lenticular galaxy, 2MASX J10405643-0103584, resides at the center of a low-mass (M 500 = 1014 M ⊙) galaxy cluster. This represents the first conclusive evidence that a superluminous disk galaxy is the central BCG of a galaxy cluster. We speculate that the progenitor of 2MASX J10405643-0103584 was an elliptical galaxy, whose extended disk was re-formed due to the merger of galaxies. We exclude the possibility that the other four superluminous disk galaxies reside at the center of galaxy clusters, as their projected distance from the cluster center is 150–1070 kpc, which corresponds to (0.27–1.18)R 500. We conclude that these clusters host quiescent massive elliptical galaxies at their center.
RELICS: Strong Lensing Analysis of the Galaxy Clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849Cibirka, NatháliaAcebron, AnaZitrin, AdiCoe, DanAgulli, IreneAndrade-Santos, FelipeBradac, MarusaFrye, BrendaLivermore, Rachael C.Mahler, GuillaumeSalmon, BrettSharon, KerenTrenti, MicheleUmetsu, KeiichiAvila, RobertoBradley, LarryCarrasco, DanielaCerny, CatherineCzakon, Nicole G.Dawson, William A.Hoag, Austin T.Huang, Kuang-HanJohnson, Traci L.Jones, ChristineKikuchihara, ShotaroLam, DanielLovisari, LorenzoMainali, RameshOesch, Pascal A.Ogaz, SaraOuchi, MasamiPast, MatthewPaterno-Mahler, RachelPeterson, AveryRyan, Russell E.Sendra-Server, IreneStark, Daniel P.Strait, VictoriaToft, SuneVulcani, BenedettaDOI: info:10.3847/1538-4357/aad2d3v. 863145
Cibirka, Nathália, Acebron, Ana, Zitrin, Adi, Coe, Dan, Agulli, Irene, Andrade-Santos, Felipe, Bradac, Marusa, Frye, Brenda, Livermore, Rachael C., Mahler, Guillaume, Salmon, Brett, Sharon, Keren, Trenti, Michele, Umetsu, Keiichi, Avila, Roberto, Bradley, Larry, Carrasco, Daniela, Cerny, Catherine, Czakon, Nicole G., Dawson, William A., Hoag, Austin T., Huang, Kuang-Han, Johnson, Traci L., Jones, Christine, Kikuchihara, Shotaro et al. 2018. "RELICS: Strong Lensing Analysis of the Galaxy Clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849." The Astrophysical Journal 863:145. https://doi.org/10.3847/1538-4357/aad2d3
ID: 148987
Type: article
Authors: Cibirka, Nathália; Acebron, Ana; Zitrin, Adi; Coe, Dan; Agulli, Irene; Andrade-Santos, Felipe; Bradac, Marusa; Frye, Brenda; Livermore, Rachael C.; Mahler, Guillaume; Salmon, Brett; Sharon, Keren; Trenti, Michele; Umetsu, Keiichi; Avila, Roberto; Bradley, Larry; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Sendra-Server, Irene; Stark, Daniel P.; Strait, Victoria; Toft, Sune; Vulcani, Benedetta
Abstract: We present a strong lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a light-traces-mass technique to uncover sets of multiple images and constrain the mass distribution of the clusters. These mass models are the first published for Abell S295 and MACS J0159.8-0849 and are improvements over previous models for Abell 697 and MACS J0025.4-1222. Our analysis for MACS J0025.4-1222 and Abell S295 shows a bimodal mass distribution supporting the merger scenarios proposed for these clusters. The updated model for MACS J0025.4-1222 suggests a substantially smaller critical area than previously estimated. For MACS J0159.8-0849 and Abell 697, we find a single peak and relatively regular morphology revealing fairly relaxed clusters. Despite being less prominent lenses, three of these clusters seem to have lensing strengths, i.e., cumulative area above certain magnification, similar to those of the Hubble Frontier Fields clusters (e.g., A(mu > 5) ~ 1--3 arcmin2, A(mu > 10) ~ 0.5--1.5 arcmin2), which in part can be attributed to their merging configurations. We make our lens models publicly available through the Mikulski Archive for Space Telescopes. Finally, using Gemini-N/GMOS spectroscopic observations, we detect a single emission line from a high-redshift J 125 ~= 25.7 galaxy candidate lensed by Abell 697. While we cannot rule out a lower-redshift solution, we interpret the line as Lyalpha at z = 5.800 ± 0.001, in agreement with its photometric redshift and dropout nature. Within this scenario, we measure a Lyalpha rest-frame equivalent width of 52 ± 22 Å and an observed Gaussian width of 117 ± 15 km s-1.
Type: article
Authors: Cibirka, Nathália; Acebron, Ana; Zitrin, Adi; Coe, Dan; Agulli, Irene; Andrade-Santos, Felipe; Bradac, Marusa; Frye, Brenda; Livermore, Rachael C.; Mahler, Guillaume; Salmon, Brett; Sharon, Keren; Trenti, Michele; Umetsu, Keiichi; Avila, Roberto; Bradley, Larry; Carrasco, Daniela; Cerny, Catherine; Czakon, Nicole G.; Dawson, William A.; Hoag, Austin T.; Huang, Kuang-Han; Johnson, Traci L.; Jones, Christine; Kikuchihara, Shotaro; Lam, Daniel; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Ouchi, Masami; Past, Matthew; Paterno-Mahler, Rachel; Peterson, Avery; Ryan, Russell E.; Sendra-Server, Irene; Stark, Daniel P.; Strait, Victoria; Toft, Sune; Vulcani, Benedetta
Abstract: We present a strong lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a light-traces-mass technique to uncover sets of multiple images and constrain the mass distribution of the clusters. These mass models are the first published for Abell S295 and MACS J0159.8-0849 and are improvements over previous models for Abell 697 and MACS J0025.4-1222. Our analysis for MACS J0025.4-1222 and Abell S295 shows a bimodal mass distribution supporting the merger scenarios proposed for these clusters. The updated model for MACS J0025.4-1222 suggests a substantially smaller critical area than previously estimated. For MACS J0159.8-0849 and Abell 697, we find a single peak and relatively regular morphology revealing fairly relaxed clusters. Despite being less prominent lenses, three of these clusters seem to have lensing strengths, i.e., cumulative area above certain magnification, similar to those of the Hubble Frontier Fields clusters (e.g., A(mu > 5) ~ 1--3 arcmin2, A(mu > 10) ~ 0.5--1.5 arcmin2), which in part can be attributed to their merging configurations. We make our lens models publicly available through the Mikulski Archive for Space Telescopes. Finally, using Gemini-N/GMOS spectroscopic observations, we detect a single emission line from a high-redshift J 125 ~= 25.7 galaxy candidate lensed by Abell 697. While we cannot rule out a lower-redshift solution, we interpret the line as Lyalpha at z = 5.800 ± 0.001, in agreement with its photometric redshift and dropout nature. Within this scenario, we measure a Lyalpha rest-frame equivalent width of 52 ± 22 Å and an observed Gaussian width of 117 ± 15 km s-1.
RELICS: A Strong Lens Model for SPT-CLJ0615--5746, a z = 0.972 ClusterPaterno-Mahler, RachelSharon, KerenCoe, DanMahler, GuillaumeCerny, CatherineJohnson, Traci L.Schrabback, TimAndrade-Santos, FelipeAvila, Roberto J.Bradac, MarusaBradley, Larry D.Carrasco, DanielaCzakon, Nicole G.Dawson, William A.Frye, Brenda L.Hoag, Austin T.Huang, Kuang-HanJones, ChristineLam, DanielLivermore, RachaelLovisari, LorenzoMainali, RameshOesch, Pascal A.Ogaz, SaraPast, MatthewPeterson, AveryRyan, Russell E.Salmon, BrettSendra-Server, IreneStark, Daniel P.Umetsu, KeiichiVulcani, BenedettaZitrin, AdiDOI: info:10.3847/1538-4357/aad239v. 863154
Paterno-Mahler, Rachel, Sharon, Keren, Coe, Dan, Mahler, Guillaume, Cerny, Catherine, Johnson, Traci L., Schrabback, Tim, Andrade-Santos, Felipe, Avila, Roberto J., Bradac, Marusa, Bradley, Larry D., Carrasco, Daniela, Czakon, Nicole G., Dawson, William A., Frye, Brenda L., Hoag, Austin T., Huang, Kuang-Han, Jones, Christine, Lam, Daniel, Livermore, Rachael, Lovisari, Lorenzo, Mainali, Ramesh, Oesch, Pascal A., Ogaz, Sara, Past, Matthew et al. 2018. "RELICS: A Strong Lens Model for SPT-CLJ0615--5746, a z = 0.972 Cluster." The Astrophysical Journal 863:154. https://doi.org/10.3847/1538-4357/aad239
ID: 148986
Type: article
Authors: Paterno-Mahler, Rachel; Sharon, Keren; Coe, Dan; Mahler, Guillaume; Cerny, Catherine; Johnson, Traci L.; Schrabback, Tim; Andrade-Santos, Felipe; Avila, Roberto J.; Bradac, Marusa; Bradley, Larry D.; Carrasco, Daniela; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda L.; Hoag, Austin T.; Huang, Kuang-Han; Jones, Christine; Lam, Daniel; Livermore, Rachael; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Past, Matthew; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: We present a lens model for the cluster SPT-CLJ0615-5746, which is the highest-redshift (z = 0.972) system in the Reionization of Lensing Clusters Survey, making it the highest-redshift cluster for which a full, strong lens model is published. We identify three systems of multiply imaged lensed galaxies, two of which we spectroscopically confirm at z = 1.358 and z = 4.013, which we use as constraints for the model. We find a foreground structure at z ~ 0.4, which we include as a second cluster-sized halo in one of our models; however, two different statistical tests find the best-fit model consists of one cluster-sized halo combined with three individually optimized galaxy-sized halos, as well as contributions from the cluster galaxies themselves. We find the total projected mass density within r = 26."7 (the region where the strong lensing constraints exist) to be M={2.51}-0.09+0.15× {10}14 M &sun;. If we extrapolate out to r 500, our projected mass density is consistent with the mass inferred from weak lensing and from the Sunyaev--Zel'dovich effect (M ~ 1015 M &sun;). This cluster is lensing a previously reported z ~ 10 galaxy, which, if spectroscopically confirmed, will be the highest-redshift strongly lensed galaxy known.
Type: article
Authors: Paterno-Mahler, Rachel; Sharon, Keren; Coe, Dan; Mahler, Guillaume; Cerny, Catherine; Johnson, Traci L.; Schrabback, Tim; Andrade-Santos, Felipe; Avila, Roberto J.; Bradac, Marusa; Bradley, Larry D.; Carrasco, Daniela; Czakon, Nicole G.; Dawson, William A.; Frye, Brenda L.; Hoag, Austin T.; Huang, Kuang-Han; Jones, Christine; Lam, Daniel; Livermore, Rachael; Lovisari, Lorenzo; Mainali, Ramesh; Oesch, Pascal A.; Ogaz, Sara; Past, Matthew; Peterson, Avery; Ryan, Russell E.; Salmon, Brett; Sendra-Server, Irene; Stark, Daniel P.; Umetsu, Keiichi; Vulcani, Benedetta; Zitrin, Adi
Abstract: We present a lens model for the cluster SPT-CLJ0615-5746, which is the highest-redshift (z = 0.972) system in the Reionization of Lensing Clusters Survey, making it the highest-redshift cluster for which a full, strong lens model is published. We identify three systems of multiply imaged lensed galaxies, two of which we spectroscopically confirm at z = 1.358 and z = 4.013, which we use as constraints for the model. We find a foreground structure at z ~ 0.4, which we include as a second cluster-sized halo in one of our models; however, two different statistical tests find the best-fit model consists of one cluster-sized halo combined with three individually optimized galaxy-sized halos, as well as contributions from the cluster galaxies themselves. We find the total projected mass density within r = 26."7 (the region where the strong lensing constraints exist) to be M={2.51}-0.09+0.15× {10}14 M &sun;. If we extrapolate out to r 500, our projected mass density is consistent with the mass inferred from weak lensing and from the Sunyaev--Zel'dovich effect (M ~ 1015 M &sun;). This cluster is lensing a previously reported z ~ 10 galaxy, which, if spectroscopically confirmed, will be the highest-redshift strongly lensed galaxy known.
Deep VLA Observations of the Cluster 1RXS J0603.3+4214 in the Frequency Range of 1--2 GHzRajpurohit, K.Hoeft, M.van Weeren, R. J.Rudnick, L.Röttgering, H. J. A.Forman, W. R.Brüggen, M.Croston, J. H.Andrade-Santos, F.Dawson, W. A.Intema, H. T.Kraft, R. P.Jones, C.Jee, M. JamesDOI: info:10.3847/1538-4357/aa9f13v. 85265
Rajpurohit, K., Hoeft, M., van Weeren, R. J., Rudnick, L., Röttgering, H. J. A., Forman, W. R., Brüggen, M., Croston, J. H., Andrade-Santos, F., Dawson, W. A., Intema, H. T., Kraft, R. P., Jones, C., and Jee, M. James. 2018. "Deep VLA Observations of the Cluster 1RXS J0603.3+4214 in the Frequency Range of 1--2 GHz." The Astrophysical Journal 852:65. https://doi.org/10.3847/1538-4357/aa9f13
ID: 145767
Type: article
Authors: Rajpurohit, K.; Hoeft, M.; van Weeren, R. J.; Rudnick, L.; Röttgering, H. J. A.; Forman, W. R.; Brüggen, M.; Croston, J. H.; Andrade-Santos, F.; Dawson, W. A.; Intema, H. T.; Kraft, R. P.; Jones, C.; Jee, M. James
Abstract: We report L-band VLA observations of 1RXS J0603.3+4214, a cluster that hosts a bright radio relic, known as the Toothbrush, and an elongated giant radio halo. These new observations allow us to study the surface brightness distribution down to 1 arcsec resolution with very high sensitivity. Our images provide an unprecedented detailed view of the Toothbrush, revealing enigmatic filamentary structures. To study the spectral index distribution, we complement our analysis with published LOFAR and GMRT observations. The bright ``brush'' of the Toothbrush shows a prominent narrow ridge to its north with a sharp outer edge. The spectral index at the ridge is in the range -0.70 -0.2+0.3. The radio halo shows an average spectral index of alpha = -1.16 ± 0.05 and a slight gradient from north to south. The southernmost part of the halo is steeper and possibly related to a shock front. Excluding the southernmost part, the halo morphology agrees very well with the X-ray morphology. A power-law correlation is found between the radio and X-ray surface brightness.
Type: article
Authors: Rajpurohit, K.; Hoeft, M.; van Weeren, R. J.; Rudnick, L.; Röttgering, H. J. A.; Forman, W. R.; Brüggen, M.; Croston, J. H.; Andrade-Santos, F.; Dawson, W. A.; Intema, H. T.; Kraft, R. P.; Jones, C.; Jee, M. James
Abstract: We report L-band VLA observations of 1RXS J0603.3+4214, a cluster that hosts a bright radio relic, known as the Toothbrush, and an elongated giant radio halo. These new observations allow us to study the surface brightness distribution down to 1 arcsec resolution with very high sensitivity. Our images provide an unprecedented detailed view of the Toothbrush, revealing enigmatic filamentary structures. To study the spectral index distribution, we complement our analysis with published LOFAR and GMRT observations. The bright ``brush'' of the Toothbrush shows a prominent narrow ridge to its north with a sharp outer edge. The spectral index at the ridge is in the range -0.70 -0.2+0.3. The radio halo shows an average spectral index of alpha = -1.16 ± 0.05 and a slight gradient from north to south. The southernmost part of the halo is steeper and possibly related to a shock front. Excluding the southernmost part, the halo morphology agrees very well with the X-ray morphology. A power-law correlation is found between the radio and X-ray surface brightness.
LOFAR discovery of an ultra-steep radio halo and giant head-tail radio galaxy in Abell 1132Wilber, A.Brüggen, M.Bonafede, A.Savini, F.Shimwell, T.van Weeren, R. J.Rafferty, D.Mechev, A. P.Intema, H.Andrade-Santos, F.Clarke, A. O.Mahony, E. K.Morganti, R.Prandoni, I.Brunetti, G.Röttgering, H.Mandal, S.de Gasperin, F.Hoeft, M.DOI: info:10.1093/mnras/stx2568v. 4733536–3546
Wilber, A., Brüggen, M., Bonafede, A., Savini, F., Shimwell, T., van Weeren, R. J., Rafferty, D., Mechev, A. P., Intema, H., Andrade-Santos, F., Clarke, A. O., Mahony, E. K., Morganti, R., Prandoni, I., Brunetti, G., Röttgering, H., Mandal, S., de Gasperin, F., and Hoeft, M. 2018. "LOFAR discovery of an ultra-steep radio halo and giant head-tail radio galaxy in Abell 1132." Monthly Notices of the Royal Astronomical Society 473:3536– 3546. https://doi.org/10.1093/mnras/stx2568
ID: 145741
Type: article
Authors: Wilber, A.; Brüggen, M.; Bonafede, A.; Savini, F.; Shimwell, T.; van Weeren, R. J.; Rafferty, D.; Mechev, A. P.; Intema, H.; Andrade-Santos, F.; Clarke, A. O.; Mahony, E. K.; Morganti, R.; Prandoni, I.; Brunetti, G.; Röttgering, H.; Mandal, S.; de Gasperin, F.; Hoeft, M.
Abstract: Low-Frequency Array (LOFAR) observations at 144 MHz have revealed large-scale radio sources in the unrelaxed galaxy cluster Abell 1132. The cluster hosts diffuse radio emission on scales of ~650 kpc near the cluster centre and a head-tail (HT) radio galaxy, extending up to 1 Mpc, south of the cluster centre. The central diffuse radio emission is not seen in NRAO VLA FIRST Survey, Westerbork Northern Sky Survey, nor in C & D array VLA observations at 1.4 GHz, but is detected in our follow-up Giant Meterwave Radio Telescope (GMRT) observations at 325 MHz. Using LOFAR and GMRT data, we determine the spectral index of the central diffuse emission to be alpha = -1.75 ± 0.19 (S ∝ nualpha). We classify this emission as an ultra-steep spectrum radio halo and discuss the possible implications for the physical origin of radio haloes. The HT radio galaxy shows narrow, collimated emission extending up to 1 Mpc and another 300 kpc of more diffuse, disturbed emission, giving a full projected linear size of 1.3 Mpc - classifying it as a giant radio galaxy (GRG) and making it the longest HT found to date. The head of the GRG coincides with an elliptical galaxy (SDSS J105851.01+564308.5) belonging to Abell 1132. In our LOFAR image, there appears to be a connection between the radio halo and the GRG. The turbulence that may have produced the halo may have also affected the tail of the GRG. In turn, the GRG may have provided seed electrons for the radio halo.
Type: article
Authors: Wilber, A.; Brüggen, M.; Bonafede, A.; Savini, F.; Shimwell, T.; van Weeren, R. J.; Rafferty, D.; Mechev, A. P.; Intema, H.; Andrade-Santos, F.; Clarke, A. O.; Mahony, E. K.; Morganti, R.; Prandoni, I.; Brunetti, G.; Röttgering, H.; Mandal, S.; de Gasperin, F.; Hoeft, M.
Abstract: Low-Frequency Array (LOFAR) observations at 144 MHz have revealed large-scale radio sources in the unrelaxed galaxy cluster Abell 1132. The cluster hosts diffuse radio emission on scales of ~650 kpc near the cluster centre and a head-tail (HT) radio galaxy, extending up to 1 Mpc, south of the cluster centre. The central diffuse radio emission is not seen in NRAO VLA FIRST Survey, Westerbork Northern Sky Survey, nor in C & D array VLA observations at 1.4 GHz, but is detected in our follow-up Giant Meterwave Radio Telescope (GMRT) observations at 325 MHz. Using LOFAR and GMRT data, we determine the spectral index of the central diffuse emission to be alpha = -1.75 ± 0.19 (S ∝ nualpha). We classify this emission as an ultra-steep spectrum radio halo and discuss the possible implications for the physical origin of radio haloes. The HT radio galaxy shows narrow, collimated emission extending up to 1 Mpc and another 300 kpc of more diffuse, disturbed emission, giving a full projected linear size of 1.3 Mpc - classifying it as a giant radio galaxy (GRG) and making it the longest HT found to date. The head of the GRG coincides with an elliptical galaxy (SDSS J105851.01+564308.5) belonging to Abell 1132. In our LOFAR image, there appears to be a connection between the radio halo and the GRG. The turbulence that may have produced the halo may have also affected the tail of the GRG. In turn, the GRG may have provided seed electrons for the radio halo.
The Fraction of Cool-core Clusters in X-Ray versus SZ Samples Using Chandra ObservationsAndrade-Santos, FelipeJones, ChristineForman, William R.Lovisari, LorenzoVikhlinin, Alexeyvan Weeren, Reinout J.Murray, Stephen S.Arnaud, MoniquePratt, Gabriel W.Démoclès, JessicaKraft, RalphMazzotta, PasqualeBöhringer, HansChon, GayoungGiacintucci, SimonaClarke, Tracy E.Borgani, StefanoDavid, LarryDouspis, MarianPointecouteau, EtienneDahle, HåkonBrown, SheaAghanim, NabilaRasia, ElenaDOI: info:10.3847/1538-4357/aa7461v. 84376
Andrade-Santos, Felipe, Jones, Christine, Forman, William R., Lovisari, Lorenzo, Vikhlinin, Alexey, van Weeren, Reinout J., Murray, Stephen S., Arnaud, Monique, Pratt, Gabriel W., Démoclès, Jessica, Kraft, Ralph, Mazzotta, Pasquale, Böhringer, Hans, Chon, Gayoung, Giacintucci, Simona, Clarke, Tracy E., Borgani, Stefano, David, Larry, Douspis, Marian, Pointecouteau, Etienne, Dahle, Håkon, Brown, Shea, Aghanim, Nabila, and Rasia, Elena. 2017. "The Fraction of Cool-core Clusters in X-Ray versus SZ Samples Using Chandra Observations." The Astrophysical Journal 843:76. https://doi.org/10.3847/1538-4357/aa7461
ID: 143818
Type: article
Authors: Andrade-Santos, Felipe; Jones, Christine; Forman, William R.; Lovisari, Lorenzo; Vikhlinin, Alexey; van Weeren, Reinout J.; Murray, Stephen S.; Arnaud, Monique; Pratt, Gabriel W.; Démoclès, Jessica; Kraft, Ralph; Mazzotta, Pasquale; Böhringer, Hans; Chon, Gayoung; Giacintucci, Simona; Clarke, Tracy E.; Borgani, Stefano; David, Larry; Douspis, Marian; Pointecouteau, Etienne; Dahle, Håkon; Brown, Shea; Aghanim, Nabila; Rasia, Elena
Abstract: We derive and compare the fractions of cool-core clusters in the Planck Early Sunyaev-Zel’dovich sample of 164 clusters with z≤slant 0.35 and in a flux-limited X-ray sample of 100 clusters with z≤slant 0.30, using Chandra observations. We use four metrics to identify cool-core clusters: (1) the concentration parameter, which is the ratio of the integrated emissivity profile within 0.15 r 500 to that within r 500; (2) the ratio of the integrated emissivity profile within 40 kpc to that within 400 kpc; (3) the cuspiness of the gas density profile, which is the negative of the logarithmic derivative of the gas density with respect to the radius, measured at 0.04 r 500; and (4) the central gas density, measured at 0.01 r 500. We find that the sample of X-ray-selected clusters, as characterized by each of these metrics, contains a significantly larger fraction of cool-core clusters compared to the sample of SZ-selected clusters (44% ± 7% versus 28% ± 4% using the concentration parameter in the 0.15-1.0 r 500 range, 61% ± 8% versus 36% ± 5% using the concentration parameter in the 40-400 kpc range, 64% ± 8% versus 38% ± 5% using the cuspiness, and 53% ± 7% versus 39 ± 5% using the central gas density). Qualitatively, cool-core clusters are more X-ray luminous at fixed mass. Hence, our X-ray, flux-limited sample, compared to the approximately mass-limited SZ sample, is overrepresented with cool-core clusters. We describe a simple quantitative model that uses the excess luminosity of cool-core clusters compared to non-cool-core clusters at fixed mass to successfully predict the observed fraction of cool-core clusters in X-ray-selected samples.
Type: article
Authors: Andrade-Santos, Felipe; Jones, Christine; Forman, William R.; Lovisari, Lorenzo; Vikhlinin, Alexey; van Weeren, Reinout J.; Murray, Stephen S.; Arnaud, Monique; Pratt, Gabriel W.; Démoclès, Jessica; Kraft, Ralph; Mazzotta, Pasquale; Böhringer, Hans; Chon, Gayoung; Giacintucci, Simona; Clarke, Tracy E.; Borgani, Stefano; David, Larry; Douspis, Marian; Pointecouteau, Etienne; Dahle, Håkon; Brown, Shea; Aghanim, Nabila; Rasia, Elena
Abstract: We derive and compare the fractions of cool-core clusters in the Planck Early Sunyaev-Zel’dovich sample of 164 clusters with z≤slant 0.35 and in a flux-limited X-ray sample of 100 clusters with z≤slant 0.30, using Chandra observations. We use four metrics to identify cool-core clusters: (1) the concentration parameter, which is the ratio of the integrated emissivity profile within 0.15 r 500 to that within r 500; (2) the ratio of the integrated emissivity profile within 40 kpc to that within 400 kpc; (3) the cuspiness of the gas density profile, which is the negative of the logarithmic derivative of the gas density with respect to the radius, measured at 0.04 r 500; and (4) the central gas density, measured at 0.01 r 500. We find that the sample of X-ray-selected clusters, as characterized by each of these metrics, contains a significantly larger fraction of cool-core clusters compared to the sample of SZ-selected clusters (44% ± 7% versus 28% ± 4% using the concentration parameter in the 0.15-1.0 r 500 range, 61% ± 8% versus 36% ± 5% using the concentration parameter in the 40-400 kpc range, 64% ± 8% versus 38% ± 5% using the cuspiness, and 53% ± 7% versus 39 ± 5% using the central gas density). Qualitatively, cool-core clusters are more X-ray luminous at fixed mass. Hence, our X-ray, flux-limited sample, compared to the approximately mass-limited SZ sample, is overrepresented with cool-core clusters. We describe a simple quantitative model that uses the excess luminosity of cool-core clusters compared to non-cool-core clusters at fixed mass to successfully predict the observed fraction of cool-core clusters in X-ray-selected samples.
Recovering galaxy cluster gas density profiles with XMM-Newton and ChandraBartalucci, I.Arnaud, M.Pratt, G. W.Vikhlinin, A.Pointecouteau, E.Forman, W. R.Jones, C.Mazzotta, P.Andrade-Santos, F.DOI: info:10.1051/0004-6361/201731689v. 608A88
Bartalucci, I., Arnaud, M., Pratt, G. W., Vikhlinin, A., Pointecouteau, E., Forman, W. R., Jones, C., Mazzotta, P., and Andrade-Santos, F. 2017. "Recovering galaxy cluster gas density profiles with XMM-Newton and Chandra." Astronomy and Astrophysics 608:A88. https://doi.org/10.1051/0004-6361/201731689
ID: 145669
Type: article
Authors: Bartalucci, I.; Arnaud, M.; Pratt, G. W.; Vikhlinin, A.; Pointecouteau, E.; Forman, W. R.; Jones, C.; Mazzotta, P.; Andrade-Santos, F.
Abstract: We examined the reconstruction of galaxy cluster radial density profiles obtained from Chandra and XMM-Newton X-ray observations, using high quality data for a sample of twelve objects covering a range of morphologies and redshifts. By comparing the results obtained from the two observatories and by varying key aspects of the analysis procedure, we examined the impact of instrumental effects and of differences in the methodology used in the recovery of the density profiles. We find that the final density profile shape is particularly robust. We adapted the photon weighting vignetting correction method developed for XMM-Newton for use with Chandra data, and confirm that the resulting Chandra profiles are consistent with those corrected a posteriori for vignetting effects. Profiles obtained from direct deprojection and those derived using parametric models are consistent at the 1% level. At radii larger than 6´´, the agreement between Chandra and XMM-Newton is better than 1%, confirming an excellent understanding of the XMM-Newton PSF. Furthermore, we find no significant energy dependence. The impact of the well-known offset between Chandra and XMM-Newton gas temperature determinations on the density profiles is found to be negligible. However, we find an overall normalisation offset in density profiles of the order of 2.5%, which is linked to absolute flux cross-calibration issues. As a final result, the weighted ratios of Chandra to XMM-Newton gas masses computed at R2500 and R500 are r = 1.03 ± 0.01 and r = 1.03 ± 0.03, respectively. Our study confirms that the radial density profiles are robustly recovered, and that any differences between Chandra and XMM-Newton can be constrained to the 2.5% level, regardless of the exact data analysis details. These encouraging results open the way for the true combination of X-ray observations of galaxy clusters, fully leveraging the high resolution of Chandra and the high throughput of XMM-Newton.
Type: article
Authors: Bartalucci, I.; Arnaud, M.; Pratt, G. W.; Vikhlinin, A.; Pointecouteau, E.; Forman, W. R.; Jones, C.; Mazzotta, P.; Andrade-Santos, F.
Abstract: We examined the reconstruction of galaxy cluster radial density profiles obtained from Chandra and XMM-Newton X-ray observations, using high quality data for a sample of twelve objects covering a range of morphologies and redshifts. By comparing the results obtained from the two observatories and by varying key aspects of the analysis procedure, we examined the impact of instrumental effects and of differences in the methodology used in the recovery of the density profiles. We find that the final density profile shape is particularly robust. We adapted the photon weighting vignetting correction method developed for XMM-Newton for use with Chandra data, and confirm that the resulting Chandra profiles are consistent with those corrected a posteriori for vignetting effects. Profiles obtained from direct deprojection and those derived using parametric models are consistent at the 1% level. At radii larger than 6´´, the agreement between Chandra and XMM-Newton is better than 1%, confirming an excellent understanding of the XMM-Newton PSF. Furthermore, we find no significant energy dependence. The impact of the well-known offset between Chandra and XMM-Newton gas temperature determinations on the density profiles is found to be negligible. However, we find an overall normalisation offset in density profiles of the order of 2.5%, which is linked to absolute flux cross-calibration issues. As a final result, the weighted ratios of Chandra to XMM-Newton gas masses computed at R2500 and R500 are r = 1.03 ± 0.01 and r = 1.03 ± 0.03, respectively. Our study confirms that the radial density profiles are robustly recovered, and that any differences between Chandra and XMM-Newton can be constrained to the 2.5% level, regardless of the exact data analysis details. These encouraging results open the way for the true combination of X-ray observations of galaxy clusters, fully leveraging the high resolution of Chandra and the high throughput of XMM-Newton.