Browsing by Author "Franz E. Bauer"
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- ItemAGN Feedback and Star Formation of Quasar Host Galaxies: Insights from the Molecular Gas(2020) Jinyi Shangguan; Luis C. Ho; Franz E. Bauer; Ran Wang; Ezequiel TreisterMolecular gas serves as a key probe of the complex interplay between black hole accretion and star formation in the host galaxies of active galactic nuclei (AGNs). We use CO(2-1) observations from a new Atacama Large Millimeter/submillimeter Array survey, in conjunction with literature measurements, to investigate the molecular gas properties of a representative sample of 40z < 0.3 Palomar-Green quasars, the largest and most sensitive study of molecular gas emission to date for nearby quasars. We find that the AGN luminosity correlates with both the CO luminosity and black hole mass, suggesting that AGN activity is loosely coupled to the cold gas reservoir of the host. The observed strong correlation between host galaxy total infrared luminosity and AGN luminosity arises from their common dependence on the molecular gas. We argue that the total infrared luminosity, at least for low-redshift quasars, can be used to derive reliable star formation rates for the host galaxy. The host galaxies of low-redshift quasars have a molecular gas content similar to that of star-forming galaxies of comparable stellar mass. Moreover, they share similar gas kinematics, as evidenced by their CO Tully-Fisher relation and the absence of detectable molecular outflows down to sensitive limits. There is no sign that AGN feedback quenches star formation for the quasars in our sample. On the contrary, the abundant gas supply forms stars prodigiously, at a rate that places most of them above the star-forming main sequence and with an efficiency that rivals that of starburst systems.
- ItemBASS. XXI. The Data Release 2 Overview(2022) Michael J. Koss; Benny Trakhtenbrot; Claudio Ricci; Franz E. Bauer; Ezequiel Treister; Richard Mushotzky; C. Megan Urry; Tonima T. Ananna; Mislav Baloković; Jakob S. den Brok; S. Bradley Cenko; Fiona Harrison; Kohei Ichikawa; Isabella Lamperti; Amy Lein; Julian E. Mejía-Restrepo; Kyuseok Oh; Fabio Pacucci; Ryan W. Pfeifle; Meredith C. Powell; George C. Privon; Federica Ricci; Mara Salvato; Kevin Schawinski; Taro Shimizu; Krista L. Smith; Daniel Stern
- ItemBASS. XXII. The BASS DR2 AGN Catalog and Data(2022) Michael J. Koss; Claudio Ricci; Benny Trakhtenbrot; Kyuseok Oh; Jakob S. den Brok; Julian E. Mejía-Restrepo; Daniel Stern; George C. Privon; Ezequiel Treister; Meredith C. Powell; Richard Mushotzky; Franz E. Bauer; Tonima T. Ananna; Mislav Baloković; Rudolf E. Bär; George Becker; Patricia Bessiere; Leonard Burtscher; Turgay Caglar; Enrico Congiu; Phil Evans; Fiona Harrison; Marianne Heida; Kohei Ichikawa; Nikita Kamraj; Isabella Lamperti; Fabio Pacucci; Federica Ricci; Rogério Riffel; Alejandra F. Rojas; Kevin Schawinski; Matthew J. Temple; C. Megan Urry; Sylvain Veilleux; Jonathan Williams
- ItemBASS. XXIX. The Near-infrared View of the Broad-line Region (BLR): The Effects of Obscuration in BLR Characterization*(2022) Federica Ricci; Ezequiel Treister; Franz E. Bauer; Julian E. Mejía-Restrepo; Michael J. Koss; Jakob S. den Brok; Mislav Baloković; Rudolf Bär; Patricia Bessiere; Turgay Caglar; Fiona Harrison; Kohei Ichikawa; Darshan Kakkad; Isabella Lamperti; Richard Mushotzky; Kyuseok Oh; Meredith C. Powell; George C. Privon; Claudio Ricci; Rogerio Riffel; Alejandra F. Rojas; Eleonora Sani; Krista L. Smith; Daniel Stern; Benny Trakhtenbrot; C. Megan Urry; Sylvain Veilleux
- ItemBASS. XXX. Distribution Functions of DR2 Eddington Ratios, Black Hole Masses, and X-Ray Luminosities(2022) Tonima Tasnim Ananna; Anna K. Weigel; Benny Trakhtenbrot; Michael J. Koss; C. Megan Urry; Claudio Ricci; Ryan C. Hickox; Ezequiel Treister; Franz E. Bauer; Yoshihiro Ueda; Richard Mushotzky; Federica Ricci; Kyuseok Oh; Julian E. Mejía-Restrepo; Jakob Den Brok; Daniel Stern; Meredith C. Powell; Turgay Caglar; Kohei Ichikawa; O. Ivy Wong; Fiona A. Harrison; Kevin Schawinski
- ItemBAT AGN Spectroscopic Survey. XX. Molecular Gas in Nearby Hard-X-Ray-selected AGN Galaxies(2021) Michael J. Koss; Benjamin Strittmatter; Isabella Lamperti; Taro Shimizu; Benny Trakhtenbrot; Amelie Saintonge; Ezequiel Treister; Claudia Cicone; Richard Mushotzky; Kyuseok Oh; Claudio Ricci; Daniel Stern; Tonima Tasnim Ananna; Franz E. Bauer; George C. Privon; Rudolf E. Bär; Carlos De Breuck; Fiona Harrison; Kohei Ichikawa; Meredith C. Powell; David Rosario; David B. Sanders; Kevin Schawinski; Li Shao; C. Megan Urry; Sylvain VeilleuxWe present the host-galaxy molecular gas properties of a sample of 213 nearby (0.01.<.z.<.0.05) hard-X-rayselected active galactic nucleus (AGN) galaxies, drawn from the 70-month catalog of Swift's Burst Alert Telescope (BAT), with 200 new CO(2-1) line measurements obtained with the James Clerk Maxwell Telescope and the Atacama Pathfinder Experiment telescope. We find that AGN in massive galaxies (log(M*/M-circle dot) > 10.5) tend to have more molecular gas and higher gas fractions than inactive galaxies matched in stellar mass. When matched in star formation, we find AGN galaxies show no difference from inactive galaxies, with no evidence that AGN feedback affects the molecular gas. The higher molecular gas content is related to AGN galaxies hosting a population of gas-rich early types with an order of magnitude more molecular gas and a smaller fraction of quenched, passive galaxies (similar to 5% versus 49%) compared to inactive galaxies. The likelihood of a given galaxy hosting an AGN (L-bol > 10(44) erg s(-1)) increases by similar to 10-100 between a molecular gas mass of 10(8.7)M(circle dot) and 10(10.2)M(circle dot). AGN galaxies with a higher Eddington ratio (log(L/L-Edd) > -1.3) tend to have higher molecular gas masses and gas fractions. The log(N-H/cm(-2)) > 23.4) of AGN galaxies with higher column densities are associated with lower depletion timescales and may prefer hosts with more gas centrally concentrated in the bulge that may be more prone to quenching than galaxy-wide molecular gas. The significant average link of host-galaxy molecular gas supply to supermassive black hole (SMBH) growth may naturally lead to the general correlations found between SMBHs and their host galaxies, such as the correlations between SMBH mass and bulge properties, and the redshift evolution of star formation and SMBH growth.
- ItemCompact Molecular Gas Distribution in Quasar Host Galaxies(2021) Juan Molina; Ran Wang; Jinyi Shangguan; Luis C. Ho; Franz E. Bauer; Ezequiel Treister; Yali ShaoWe use Atacama Large Millimeter/submillimeter Array CO (2-1) observations of six low-redshift Palomar-Green quasars to study the distribution and kinematics of the molecular gas of their host galaxies at kiloparsec-scale resolution. While the molecular gas content, molecular gas fraction, and star formation rates are similar to those of nearby massive, star-forming galaxies, the quasar host galaxies possess exceptionally compact, disky molecular gas distributions with a median half-light radius of 1.8 kpc and molecular gas mass surface densities greater than or similar to 22 M pc(-2). While the overall velocity field of the molecular gas is dominated by regular rotation out to large radii, with ratio of rotation velocity to velocity dispersion greater than or similar to 9, the nuclear region displays substantial kinematic complexity associated with small-scale substructure in the gas distribution. A tilted-ring analysis reveals that the kinematic and photometric position angles are misaligned on average by similar to 34 degrees 26 degrees and provides evidence of kinematic twisting. These observations provide tantalizing clues to the detailed physical conditions of the circumnuclear environments of actively accreting supermassive black holes.
- ItemLAGER Lyα Luminosity Function at z ∼ 7: Implications for Reionization(2022) Isak G. B. Wold; Sangeeta Malhotra; James Rhoads; Junxian Wang; Weida Hu; Lucia A. Perez; Zhen-Ya Zheng; Ali Ahmad Khostovan; Alistair R. Walker; L. Felipe Barrientos; Jorge González-López; Santosh Harish; Leopoldo Infante; Chunyan Jiang; John Pharo; Cristóbal Moya-Sierralta; Franz E. Bauer; Gaspar Galaz; Francisco Valdes; Huan YangWe present a new measurement of the Ly alpha luminosity function (LF) at redshift z = 6.9, finding moderate evolution from z = 5.7 that is consistent with a fully or largely ionized z similar to 7 intergalactic medium. Our result is based on four fields of the LAGER (Lyman Alpha Galaxies in the Epoch of Reionization) project. Our survey volume of 6.1 x 10(6) Mpc(3) is double that of the next largest z similar to 7 survey. We combine two new LAGER fields (WIDE12 and GAMA15A) with two previously reported LAGER fields (COSMOS and CDFS). In the new fields, we identify N = 95 new z = 6.9 Ly alpha emitter (LAEs) candidates, characterize our survey's completeness and reliability, and compute Ly alpha LFs. The best-fit Schechter LF parameters for all four LAGER fields are in good general agreement. Two fields (COSMOS and WIDE12) show evidence for a bright-end excess above the Schechter function fit. We find that the Ly alpha luminosity density declines at the same rate as the UV continuum LF from z = 5.7 to 6.9. This is consistent with an intergalactic medium that was fully ionized as early as redshift z similar to 7 or with a volume-averaged neutral hydrogen fraction of x (H I) < 0.33 at 1 sigma.
- ItemThe Complex Gaseous and Stellar Environments of the Nearby Dual Active Galactic Nucleus Mrk 739(2021) Dusán Tubín; Ezequiel Treister; Giuseppe D’Ago; Giacomo Venturi; Franz E. Bauer; George C. Privon; Michael J. Koss; Federica Ricci; Julia M. Comerford; Francisco Müller-SánchezWe present integral field spectroscopic observations of the nearby (z similar to 0.03) dual active galactic nuclei (AGNs) Mrk 739, whose projected nuclear separation is similar to 3.4 kpc, obtained with the Multi Unit Spectroscopic Explorer at the Very Large Telescope. We find that the galaxy has an extended AGN-ionized emission-line region extending up to similar to 20 kpc away from the nuclei, while star-forming regions are more centrally concentrated within 2-3 kpc. We model the kinematics of the ionized gas surrounding the eastern nucleus using a circular disk profile, resulting in a peak velocity of 237(28)(+26) km s(-1) at a distance of similar to 1.2 kpc. The enclosed dynamical mass within 1.2 kpc is logM(M-circle dot) = 10.20 +/- 0.06, similar to 1000 times larger than the estimated supermassive black hole (SMBH) mass of Mrk 739E. The morphology and dynamics of the system are consistent with an early stage of the collision, where the foreground galaxy (Mrk 739W) is a young star-forming galaxy in an ongoing first passage with its background companion (Mrk 739E). Since the SMBH in Mrk 739W does not show evidence of being rapidly accreting, we claim that the northern spiral arms of Mrk 739W are ionized by the nuclear activity of Mrk 739E.