4 results on '"John D. Silverman"'
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2. Obscured AGN at 1.5 <z <3.0 from the zCOSMOS-deep Survey I. Properties of the emitting gas in the narrow-line region
- Author
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V. Mainieri, M. Bolzonella, Angela Bongiorno, E. Perez Montero, E. Zucca, Roberto Gilli, Simon J. Lilly, Anton M. Koekemoer, Christian Maier, Rongmon Bordoloi, V. Le Brun, Karina Caputi, M. Mignoli, G. Zamorani, Bianca Garilli, Andrea Cimatti, Cristian Vignali, Y. Peng, C. Diener, S. Bardelli, O. Le Fèvre, Anna Feltre, John D. Silverman, Francesco Calura, Istituto Nazionale di Astrofisica, European Research Council, National Key Research and Development Program (China), National Science Foundation (US), Astronomy, ITA, Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
ACTIVE GALACTIC NUCLEI ,EMISSION-LINES ,Active galactic nucleus ,Radio galaxy ,Metallicity ,Astrophysics::High Energy Astrophysical Phenomena ,MASS-METALLICITY RELATION ,galaxies: active ,galaxies [x-rays] ,CHEMICAL EVOLUTION ,RADIO GALAXIES ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,LUMINOSITY RELATIONSHIP ,01 natural sciences ,formation [line] ,SUPERMASSIVE BLACK-HOLES ,emission lines [quasars] ,0103 physical sciences ,STAR-FORMING GALAXIES ,fundamental parameters [galaxies] ,Emission spectrum ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,evolution [galaxies] ,Physics ,Supermassive black hole ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,NEBULAR EMISSION ,Astronomy and Astrophysics ,galaxies: fundamental parameters ,Astrophysics - Astrophysics of Galaxies ,FUNDAMENTAL RELATION ,Galaxy ,Redshift ,quasars: emission lines ,X-rays: galaxies ,[SDU]Sciences of the Universe [physics] ,Space and Planetary Science ,active [galaxies] ,Microturbulence ,line: formation ,galaxies: evolution - Abstract
The physics and demographics of high-redshift obscured active galactic nuclei (AGN) is still scarcely investigated. New samples of such objects, selected with different techniques, can provide useful insights into their physical properties. Aims. With the goal to determine the properties of the gas in the emitting region of type 2 AGN, in particular, the gas metal content, we exploit predictions from photoionization models, including new parameterizations for the distance of gas distribution from the central source and internal microturbulence in the emitting clouds, to interpret rest-frame UV spectral data. Methods. We selected a sample of 90 obscured (type 2) AGN with 1.45 ≤ z ≤ 3.05 from the zCOSMOS-deep galaxy sample by 5σ detection of the high-ionization C iv λ1549 narrow emission line. This feature in a galaxy spectrum is often associated with nuclear activity, and the selection effectiveness has also been confirmed by diagnostic diagrams based on utraviolet (UV) emission-line ratios. We applied the same selection technique and collected a sample of 102 unobscured (type 1) AGN. Taking advantage of the large amount of multiband data available in the COSMOS field, we investigated the properties of the Civ-selected type 2 AGN, focusing on their host galaxies, X-ray emission, and UV emission lines. Finally, we investigated the physical properties of the ionized gas in the narrow-line region (NLR) of this type 2 AGN sample by combining the analysis of strong UV emission lines with predictions from photoionization models. Results. We find that in order to successfully reproduce the relative intensity of UV emission lines of the selected high-z type 2 AGN, two new ingredients in the photoionization models are fundamental: small inner radii of the NLR (≈90 pc for LAGN = 1045 erg s−1 ), and the internal dissipative microturbulence of the gas-emitting clouds (with vmicr ≈ 100 km s−1 ). With these modified models, we compute the gas-phase metallicity of the NLR, and our measurements indicate a statistically significant evolution of the metal content with redshift. Finally, we do not observe a strong relationship between the NLR gas metallicity and the stellar mass of the host galaxy in our Civ-selected type 2 AGN sample.© ESO 2019, We acknowledge financial support from the agreement ASI-INAF n. 2017-14-H.O. A.F. acknowledges support from the ERC via an Advanced Grant under grant agreement no. 321323-NEOGAL and no. 339659- MUSICOS. A.C. acknowledges the support from the grants PRIN-MIUR 2015 and ASI n.I/023/12/0 and ASI n.2018-23-HH.0. Y.P. acknowledges National Key R&D Program of China Grant 2016YFA0400702, and NSFC Grant No. 11773001 and 11721303.
- Published
- 2019
3. The cosmic evolution of oxygen and nitrogen abundances in star-forming galaxies over the past 10 Gyr
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G. Zamorani, Y. Peng, L. de Ravel, E. Ricciardelli, Alvio Renzini, E. Zucca, V. Presotto, J. F. Le Borgne, P. Kampczyk, J. P. Kneib, T. Contini, Marco Scodeggio, John D. Silverman, Mikito Tanaka, P. Franzetti, Enrique Perez-Montero, L. A. M. Tasca, Angela Bongiorno, L. Tresse, O. Cucciati, S. de la Torre, C. M. Carollo, O. Le Fevre, K. Caputi, R. Pello, V. Mainieiri, M. Mignoli, A. Iovino, V. Le Brun, S. J. Lilly, B. Garilli, C. Knobel, Christian Maier, F. Lamareille, D. Vergani, S. Bardelli, M. Bolzonella, Katarina Kovac, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), E. Pérez-Montero, T. Contini, F. Lamareille, C. Maier, C. M. Carollo, J.-P. Kneib, O. Le Fèvre, S. Lilly, V. Mainieri, A. Renzini, M. Scodeggio, G. Zamorani, S. Bardelli, M. Bolzonella, A. Bongiorno, K. Caputi, O. Cucciati, S. de la Torre, L. de Ravel, P. Franzetti, B. Garilli, A. Iovino, P. Kampczyk, C. Knobel, K. Kovač, J.-F. Le Borgne, V. Le Brun, M. Mignoli, R. Pellò, Y. Peng, V. Presotto, E. Ricciardelli, J. D. Silverman, M. Tanaka, L. A. M. Tasca, L. Tresse, D. Vergani, E. Zucca, Astronomy, and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Stellar mass ,Metallicity ,MASS-METALLICITY RELATION ,chemistry.chemical_element ,FOS: Physical sciences ,PHYSICAL-PROPERTIES ,galaxies: starburst ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,COSMOLOGICAL HYDRODYNAMIC SIMULATIONS ,01 natural sciences ,Physical cosmology ,H-II REGIONS ,galaxies: abundance ,EMISSION-LINE GALAXIES ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,galaxies: fundamental parameter ,Astrophysics::Galaxy Astrophysics ,SIMILAR-TO 1.4 ,Chemical content ,Physics ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,Star formation ,Astronomy and Astrophysics ,galaxies: fundamental parameters ,VLT DEEP SURVEY ,CHEMICAL ABUNDANCES ,Nitrogen ,Redshift ,Galaxy ,chemistry ,Space and Planetary Science ,DIGITAL SKY SURVEY ,galaxies: abundances ,galaxies: evolution ,STELLAR MASS ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The chemical evolution of galaxies on a cosmological timescale is still a matter of debate despite the increasing number of available data provided by spectroscopic surveys of star-forming galaxies at different redshifts. The fundamental relations involving metallicity, such as the mass-metallicity relation (MZR) or the fundamental-metallicity relation, give controversial results about the reality of evolution of the chemical content of galaxies at a given stellar mass. In this work we shed some light on this issue using the completeness reached by the 20k bright sample of the zCOSMOS survey and using for the first time the nitrogen-to-oxygen ratio (N/O) as a tracer of the gas phase chemical evolution of galaxies that is independent of the star formation rate. Emission-line galaxies both in the SDSS and 20k zCOSMOS bright survey were used to study the evolution from the local Universe of the $MZR up to a redshift of 1.32 and the relation between stellar mass and nitrogen-to-oxygen ratio (MNOR) up to a redshift of 0.42 using the N2S2 parameter. All the physical properties derived from stellar continuum and gas emission-lines, including stellar mass, star formation rates, metallicity and N/O, were calculated in a self-consistent way over the full redshift range. We confirm the trend to find lower metallicities in galaxies of a given stellar mass in a younger Universe. This trend is even observed when taking possible selection effects into account that are due to the observed larger median star formation rates for galaxies at higher redshifts. We also find a significant evolution of the MNOR up to z = 0.4. Taking the slope of the O/H vs. N/O relation into account for the secondary-nitrogen production regime, the observed evolution of the MNOR is consistent with the trends found for both the MZR and its equivalent relation using new expressions to reduce its dependence on SFR., Comment: 15 pages, 13 figures. Accepted for publication in Astronomy & Astrophysics. Replaced to match published version and references corrected
- Published
- 2013
4. GOODS-ALMA: The slow downfall of star formation in z = 2–3 massive galaxies
- Author
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Mengyuan Xiao, Neil M. Nagar, M. Franco, David Elbaz, R. T. Coogan, David M. Alexander, Hanae Inami, Guilaine Lagache, Casey Papovich, Stéphanie Juneau, Ricardo Demarco, Georgios E. Magdis, L. Zhou, C. Gómez-Guijarro, James Mullaney, Xinwen Shu, Laure Ciesla, Benjamin Magnelli, Kentaro Motohara, Steven L. Finkelstein, E. Daddi, Wiphu Rujopakarn, Corentin Schreiber, Frédéric Bournaud, Mauro Giavalisco, Tao Wang, Henry C. Ferguson, Matthieu Béthermin, Ranga-Ram Chary, Daisuke Iono, Mark Sargent, Koryo Okumura, Mark Dickinson, Lihwai Lin, Maurilio Pannella, John D. Silverman, Alexandra Pope, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Chinese Academy of Agricultural Mechanization Sciences (CCCME), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Department of Physics [Oxford], University of Oxford [Oxford], Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), National Optical Astronomy Observatory (NOAO), Universidad de Concepción [Chile], Department of Physics [Durham University], Durham University, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), University of California [San Francisco] (UCSF), University of California, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Infrared Processing and Analysis Center (IPAC), California Institute of Technology (CALTECH), Max-Planck-Institut für Extraterrestrische Physik (MPE), European Space Agency (Baltimore) Space Telescope Science Institute (ESA), Department of Astronomy [Austin], University of Texas at Austin [Austin], Department of Astronomy [Amherst], University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS)-University of Massachusetts System (UMASS), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), Academia Sinica, Institute of Astronomy, Graduate School of Science, The University of Tokyo (UTokyo), Department of Physics and Astronomy [College Station], Texas A&M University [College Station], Chulalongkorn University [Bangkok], Kavli Institute for the Physics and Mathematics of the Universe [Tokyo] (Kavli IPMU), The University of Tokyo Institutes for Advanced Study (UTIAS), The University of Tokyo (UTokyo)-The University of Tokyo (UTokyo), European Project: 648179,H2020,ERC-2014-CoG,ConTExt(2015), European Project: 716762,ClustersXCosmo, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), University of Oxford, Universidad de Concepción - University of Concepcion [Chile], École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of California [San Francisco] (UC San Francisco), and University of California (UC)
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submillimeter: galaxies ,SPECTROSCOPIC SURVEY ,Field (physics) ,Stellar mass ,active [Galaxies] ,ULTRA DEEP FIELD ,Population ,galaxies: active ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Submillimeter Array ,star formation [Galaxies] ,high-redshift [Galaxies] ,galaxies [Submillimeter] ,galaxies: high-redshift ,0103 physical sciences ,MU-M OBSERVATIONS ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,SUBMILLIMETER GALAXIES ,FORMING GALAXIES ,010308 nuclear & particles physics ,Star formation ,COMPACT GALAXIES ,Astronomy and Astrophysics ,galaxies: fundamental parameters ,INFRARED PROPERTIES ,evolution [Galaxies] ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,LYMAN-BREAK GALAXIES ,Space and Planetary Science ,galaxies: star formation ,Astrophysics of Galaxies (astro-ph.GA) ,fundamental parameters [Galaxies] ,Elliptical galaxy ,Millimeter ,Astrophysics::Earth and Planetary Astrophysics ,FORMATION RATE DENSITY ,HIGH-REDSHIFT ,galaxies: evolution ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
We investigate the properties of a sample of 35 galaxies, detected with ALMA at 1.1 mm in the GOODS-ALMA field (area of 69 arcmin$^2$, resolution = 0.60", RMS $\simeq$ 0.18 mJy beam$^{-1}$). Using the UV-to-radio deep multiwavelength coverage of the GOODS-South field, we fit the spectral energy distributions of these galaxies to derive their key physical properties. The galaxies detected by ALMA are among the most massive at $z$ = 2-4 (M$_{\star,med}$ = 8.5$ \times$ 10$^{10}$ M$_\odot$) and are either starburst or located in the upper part of the galaxy star-forming main sequence. A significant portion of our galaxy population ($\sim$ 40%), located at $z\sim$ 2.5-3, exhibits abnormally low gas fractions. The sizes of these galaxies, measured with ALMA, are compatible with the trend between $H$-band size and stellar mass observed for $z\sim2$ elliptical galaxies suggesting that they are building compact bulges. We show that there is a strong link between star formation surface density (at 1.1 mm) and gas depletion time: the more compact a galaxy's star-forming region is, the shorter its lifetime will be (without gas replenishment). The identified compact sources associated with relatively short depletion timescales ($\sim$100 Myr), are the ideal candidates to be the progenitors of compact elliptical galaxies at $z$ $\sim$ 2., Comment: 18 pages, 8 figures, Accepted for publication in A&A
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