Browsing by Author "Sanders, David B."
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- ItemA comparative analysis of virial black hole mass estimates of moderate-luminosity active galactic nuclei using Subaru/FMOS.(2013) Matsuoka, K.; Treister, Ezequiel; Silverman, J. D.; Schramm, M.; Steinhardt C. L.; Nagao, T.; Kartaltepe, J.; Sanders, David B.; Hasinger, G.; Akiyama, M.
- ItemA Herschel Space Observatory Spectral Line Survey of Local Luminous Infrared Galaxies from 194 to 671 Microns(IOP PUBLISHING LTD, 2017) Lu, Nanyao; Zhao, Yinghe; Diaz Santos, Tanio; Kevin Xu, C.; Gao, Yu; Armus, Lee; Isaak, Kate G.; Mazzarella, Joseph M.; van der Werf, Paul P.; Appleton, Philip N.; Charmandaris, Vassilis; Evans, Aaron S.; Howell, Justin; Iwasawa, Kazushi; Leech, Jamie; Lord, Steven; Petric, Andreea O.; Privon, George C.; Sanders, David B.; Schulz, Bernhard; Surace, Jason A.We describe a Herschel Space Observatory 194-671 mu m spectroscopic survey of a sample of 121 local luminous infrared galaxies and report the fluxes of the CO J to J-1 rotational transitions for 4 <= J <= 13, the [N II] 205 mu m line, the [C I] lines at 609 and 370 mu m, as well as additional and usually fainter lines. The CO spectral line energy distributions (SLEDs) presented here are consistent with our earlier work, which was based on a smaller sample, that calls for two distinct molecular gas components in general: (i) a cold component, which emits CO lines primarily at J less than or similar to 4 and likely represents the same gas phase traced by CO (1-0), and (ii) a warm component, which dominates over the mid-J regime (4 < J less than or similar to 10) and is intimately related to current star formation. We present evidence that the CO line emission associated with an active galactic nucleus is significant only at J > 10. The flux ratios of the two [C I] lines imply modest excitation temperatures of 15-30 K; the [C I] 370 mu m line scales more linearly in flux with CO (4-3) than with CO (7-6). These findings suggest that the [C I] emission is predominantly associated with the gas component defined in (i) above. Our analysis of the stacked spectra in different far-infrared (FIR) color bins reveals an evolution of the SLED of the rotational transitions of H2O vapor as a function of the FIR color in a direction consistent with infrared photon pumping.
- ItemA massive, distant proto-cluster at z = 2.47 caught in a phase of rapid formation?(2015) Casey, C. M.; Treister, Ezequiel; Cooray, A.; Capak, P.; Fu, H.; Kovac, K.; Lilly, S.; Sanders, David B.; Scoville, Nick Z.
- ItemA population of luminous accreting black holes with hidden mergers(2018) Koss, Michael J.; Blecha, Laura; Bernhard, Phillip; Hung, Chao-Ling; Lu, Jessica R.; Trakhtenbrot, Benny; Treister, Ezequiel; Weigel, Anna; Sartori, Lia F.; Mushotzky, Richard; Schawinski, Kevin; Ricci, Claudio; Veilleux, Sylvain; Sanders, David B.
- ItemALMA [N II] 205 mu m Imaging Spectroscopy of the Interacting Galaxy System BRI 1202-0725 at Redshift 4.7(IOP PUBLISHING LTD, 2017) Lu, Nanyao; Zhao, Yinghe; Diaz Santos, Tanio; Kevin Xu, C.; Charmandaris, Vassilis; Gao, Yu; van der Werf, Paul P.; Privon, George C.; Inami, Hanae; Rigopoulou, Dimitra; Sanders, David B.; Zhu, LeiWe present the results from Atacama Large Millimeter/submillimeter Array imaging in the [N II] 205 mu m fine-structure line (hereafter [N II]) and the underlying continuum of BRI 1202-0725, an interacting galaxy system at z = 4.7, consisting of a quasi-stellar object (QSO), a submillimeter galaxy (SMG), and two Ly alpha emitters, all within similar to 25 kpc of the QSO. We detect the QSO and SMG in both [N II] and continuum. At the similar to 1 '' (or 6.6 kpc) resolution, both the QSO and SMG are resolved in [N II], with the de-convolved major axes of similar to 9 and similar to 14 kpc, respectively. In contrast, their continuum emissions are much more compact and unresolved even at an enhanced resolution of similar to 0 ''.7. The ratio of the [N II] flux to the existing CO(7-6) flux is used to constrain the dust temperature (T-dust) for a more accurate determination of the FIR luminosity L-FIR. Our best estimated T-dust equals 43 (+/- 2) K for both galaxies (assuming an emissivity index beta = 1.8). The resulting LCO(7-6)/LFIR ratios are statistically consistent with that of local luminous infrared galaxies, confirming that LCO(7-6) traces the star formation (SF) rate (SFR) in these galaxies. We estimate that the ongoing SF of the QSO (SMG) has an SFR of 5.1 (6.9) x 10(3) M-circle dot yr(-1) (+/- 30%) assuming Chabrier initial mass function, takes place within a diameter (at half maximum) of 1.3 (1.5) kpc, and will consume the existing 5 (5) x 10(11) M-circle dot of molecular gas in 10 (7) x 10(7) years.
- ItemBASS. XXXIV. A Catalog of the Nuclear Millimeter-wave Continuum Emission Properties of AGNs Constrained on Scales ≤ 100-200 pc(IOP Publishing Ltd, 2023) Kawamuro, Taiki; Ricci, Claudio; Mushotzky, Richard F.; Imanishi, Masatoshi; Bauer, Franz Erik; Ricci, Federica; Koss, Michael J.; Privon, George C.; Trakhtenbrot, Benny; Izumi, Takuma; Ichikawa, Kohei; Rojas, Alejandra F.; Smith, Krista Lynne; Shimizu, Taro; Oh, Kyuseok; den Brok, Jakob S.; Baba, Shunsuke; Balokovic, Mislav; Chang, Chin-Shin; Kakkad, Darshan; Pfeifle, Ryan W.; Temple, Matthew J.; Ueda, Yoshihiro; Harrison, Fiona; Powell, Meredith C.; Stern, Daniel; Urry, Meg; Sanders, David B.We present a catalog of the millimeter-wave (mm-wave) continuum properties of 98 nearby (z < 0.05) active galactic nuclei (AGNs) selected from the 70 month Swift/BAT hard-X-ray catalog that have precisely determined X-ray spectral properties and subarcsecond-resolution Atacama Large Millimeter/submillimeter Array Band 6 (211-275 GHz) observations as of 2021 April. Due to the hard-X-ray (>10 keV) selection, the sample is nearly unbiased for obscured systems at least up to Compton-thick-level obscuration, and provides the largest number of AGNs with high-physical-resolution mm-wave data (less than or similar to 100-200 pc). Our catalog reports emission peak coordinates, spectral indices, and peak fluxes and luminosities at 1.3 mm (230 GHz). Additionally, high-resolution mm-wave images are provided. Using the images and creating radial surface brightness profiles of mm-wave emission, we identify emission extending from the central sources and isolated blob-like emission. Flags indicating the presence of these emission features are tabulated. Among 90 AGNs with significant detections of nuclear emission, 37 AGNs (approximate to 41%) appear to have both or one of extended or blob-like components. We, in particular, investigate AGNs that show well-resolved mm-wave components and find that these seem to have a variety of origins (i.e., a jet, radio lobes, a secondary AGN, stellar clusters, a narrow-line region, galaxy disk, active star formation regions, or AGN-driven outflows), and some components have currently unclear origins.
- ItemCharacterization of Two 2 mm detected Optically Obscured Dusty Star-forming Galaxies(2022) Manning, Sinclaire M.; Casey, Caitlin M.; Zavala, Jorge A.; Magdis, Georgios E.; Drew, Patrick M.; Champagne, Jaclyn B.; Aravena, Manuel; Béthermin, Matthieu; Clements, David L.; Finkelstein, Steven L.; Fujimoto, Seiji; Hayward, Christopher C.; Hodge, Jacqueline A.; Ilbert, Olivier; Kartaltepe, Jeyhan S.; Knudsen, Kirsten K.; Koekemoer, Anton M.; Man, Allison W. S.; Sanders, David B.; Sheth, Kartik; Spilker, Justin S.; Staguhn, Johannes; Talia, Margherita; Treister, Ezequiel; Yun, Min S.The 2 mm Mapping Obscuration to Reionization with ALMA (MORA) Survey was designed to detect high-redshift (z greater than or similar to 4), massive, dusty star-forming galaxies (DSFGs). Here we present two likely high-redshift sources, identified in the survey, whose physical characteristics are consistent with a class of optical/near-infrared (OIR)-invisible DSFGs found elsewhere in the literature. We first perform a rigorous analysis of all available photometric data to fit spectral energy distributions and estimate redshifts before deriving physical properties based on our findings. Our results suggest the two galaxies, called MORA-5 and MORA-9, represent two extremes of the "OIR-dark" class of DSFGs. MORA-5 (z(phot) = 4.3(-1.3)(+1.5)) is a significantly more active starburst with a star formation rate (SFR) of 830(-190)(+340) M-circle dot yr(-1) compared to MORA-9 (z(phot) = 4.3(-1.0)(+1.3)), whose SFR is a modest 200(-60)(+250) M-circle dot yr(-1). Based on the stellar masses (M-star approximate to 10(10-11) M-circle dot), space density (n similar to (5 +/- 2) x 10(-6) Mpc(-3), which incorporates two other spectroscopically confirmed OIR-dark DSFGs in the MORA sample at z = 4.6 and z = 5.9), and gas depletion timescales (<1 Gyr) of these sources, we find evidence supporting the theory that OIR-dark DSFGs are the progenitors of recently discovered 3 < z < 4 massive quiescent galaxies.
- ItemCO (7-6), [C I] 370 mu m, and [N II] 205 mu m Line Emission of the QSO BRI1335-0417 at Redshift 4.407(2018) Lu, Nanyao; Cao, Tianwen; Diaz-Santos, Tanio; Zhao, Yinghe; Privon, George C.; Cheng, Cheng; Gao, Yu; Xu, C. Kevin; Charmandaris, Vassilis; Rigopoulou, Dimitra; Van der Werf, Paul P.; Huang, Jiasheng; Wang, Zhong; Evans, Aaron S.; Sanders, David B.
- ItemGrowing supermassive black holes in the late stages of galaxy mergers are heavily obscured.(2017) Ricci, Claudio; Bauer, Franz Erik; Treister, Ezequiel; Privon, G. C.; Schawinski, K.; Blecha, L.; Arevalo, P.; Armus, Lee; Harrison, F.; Ho, L. C.; Iwasawa, K.; Sanders, David B.; Stern, Daniel
- ItemHeavily Obscured Active Galactic Nuclei in High-redshift Luminous Infrared Galaxies.(2010) Treister, Ezequiel; Urry, C. Meg; Schawinski, Kevin; Cardamone, Carolin N.; Sanders, David B.
- ItemMajor Galaxy Mergers and the Growth of Supermassive Black Holes in Quasars.(2010) Treister, Ezequiel; Natarajan, Priyamvada; Sanders, David B.; Urry, C. Meg; Schawinski, Kevin; Kartaltepe, Jeyhan
- ItemMorphological Parameters and Associated Uncertainties for 8 Million Galaxies in the Hyper Suprime-Cam Wide Survey(2023) Ghosh, Aritra; Urry, C. Megan; Mishra, Aayush; Perreault-Levasseur, Laurence; Natarajan, Priyamvada; Sanders, David B.; Nagai, Daisuke; Tian, Chuan; Cappelluti, Nico; Kartaltepe, Jeyhan S.; Powell, Meredith C.; Rau, Amrit; Treister, EzequielWe use the Galaxy Morphology Posterior Estimation Network (GaMPEN) to estimate morphological parameters and associated uncertainties for & SIM;8 million galaxies in the Hyper Suprime-Cam Wide survey with z & LE; 0.75 and m & LE; 23. GaMPEN is a machine-learning framework that estimates Bayesian posteriors for a galaxy's bulge-to-total light ratio (L ( B )/L ( T )), effective radius (R ( e )), and flux (F). By first training on simulations of galaxies and then applying transfer learning using real data, we trained GaMPEN with <1% of our data set. This two-step process will be critical for applying machine-learning algorithms to future large imaging surveys, such as the Rubin-Legacy Survey of Space and Time, the Nancy Grace Roman Space Telescope, and Euclid. By comparing our results to those obtained using light profile fitting, we demonstrate that GaMPEN's predicted posterior distributions are well calibrated (& LSIM;5% deviation) and accurate. This represents a significant improvement over light profile fitting algorithms, which underestimate uncertainties by as much as & SIM;60%. For an overlapping subsample, we also compare the derived morphological parameters with values in two external catalogs and find that the results agree within the limits of uncertainties predicted by GaMPEN. This step also permits us to define an empirical relationship between the Sersic index and L ( B )/L ( T ) that can be used to convert between these two parameters. The catalog presented here represents a significant improvement in size (& SIM;10x), depth (& SIM;4 mag), and uncertainty quantification over previous state-of-the-art bulge+disk decomposition catalogs. With this work, we also release GaMPEN's source code and trained models, which can be adapted to other data sets.
- ItemMorphological Parameters and Associated Uncertainties for 8 Million Galaxies in the Hyper Suprime-Cam Wide Survey(Wiley, 2023) Ghosh, Aritra; Urry, C. Megan; Mishra, Aayush; Perreault-Levasseur, Laurence; Natarajan, Priyamvada; Sanders, David B.; Nagai, Daisuke; Tian, Chuan; Cappelluti, Nico; Kartaltepe, Jeyhan S.; Powell, Meredith C.; Rau, Amrit; Treister, EzequielWe use the Galaxy Morphology Posterior Estimation Network (GaMPEN) to estimate morphological parameters and associated uncertainties for & SIM;8 million galaxies in the Hyper Suprime-Cam Wide survey with z & LE; 0.75 and m & LE; 23. GaMPEN is a machine-learning framework that estimates Bayesian posteriors for a galaxy's bulge-to-total light ratio (L ( B )/L ( T )), effective radius (R ( e )), and flux (F). By first training on simulations of galaxies and then applying transfer learning using real data, we trained GaMPEN with <1% of our data set. This two-step process will be critical for applying machine-learning algorithms to future large imaging surveys, such as the Rubin-Legacy Survey of Space and Time, the Nancy Grace Roman Space Telescope, and Euclid. By comparing our results to those obtained using light profile fitting, we demonstrate that GaMPEN's predicted posterior distributions are well calibrated (& LSIM;5% deviation) and accurate. This represents a significant improvement over light profile fitting algorithms, which underestimate uncertainties by as much as & SIM;60%. For an overlapping subsample, we also compare the derived morphological parameters with values in two external catalogs and find that the results agree within the limits of uncertainties predicted by GaMPEN. This step also permits us to define an empirical relationship between the Sersic index and L ( B )/L ( T ) that can be used to convert between these two parameters. The catalog presented here represents a significant improvement in size (& SIM;10x), depth (& SIM;4 mag), and uncertainty quantification over previous state-of-the-art bulge+disk decomposition catalogs. With this work, we also release GaMPEN's source code and trained models, which can be adapted to other data sets.
- ItemNUSTAR Unveils a Heavily Obscured Low-luminosity Active Galactic Nucleus in the Luminous Infrared Galaxy NGC 6286.(2016) Ricci, Claudio; Bauer, Franz Erik; Treister, Ezequiel; Romero-Cañizales, C.; Arevalo, P.; Iwasawa, K.; Privon, G. C.; Sanders, David B.; Schawinski, K.; Stern, D.; Imanishi, M.
- ItemRest-frame optical emission lines in far-infrared-selected galaxies at z < 1.7 from the fmos-cosmos survey(2015) Kartaltepe, Jeyhan S.; Treister, Ezequiel; Sanders, David B.; Silverman, J. D.; Kashino, D.; Chu, J.; Zahid, H.; Hasinger, G.; Kewley, L.; Matsuoka, K.; Nagao, T.
- ItemThe bolometric output and host-galaxy properties of obscured AGN in the XMM-COSMOS survey.(2011) Lusso, E.; Treister, Ezequiel; Comastri, A.; Vignali, C.; Zamorani, G.; Sanders, David B.; Bolzonella, M.; Bongiorno, A.; Brusa, Marcella; Civano, Francesca; Gilli, R.
- ItemThe fraction of AGNs in major merger galaxies and its luminosity dependence.(2018) Weigel, Anna K.; Treister, Ezequiel; Schawinski, Kevin; Trakhtenbrot, Benny; Sanders, David B.
- ItemThe Great Observatories All-Sky LIRG Survey: Herschel Image Atlas and Aperture Photometry.(2017) Chu, J.; Treister, Ezequiel; Privon, George C.; Sanders, David B.; Larson, K. L.; Mazzarella, J. M.; Howell, J. H.; Díaz Santos, T.; Xu, K. C.; Paladini, R.; Schulz, B.