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Full-Text Articles in Physics
The Properties Of Post-Starburst Quasars Based On Optical Spectroscopy, Sabrina L. Cales, Michael S. Brotherton, Zhaohui Shang, Jessie C. Runnoe, Michael A. Dipompeo, Vardha Nicola Bennert, Gabriela Canalizo, Kyle D. Hiner, R. Stoll, Rajib Ganguly, Aleksandar Diamond-Stanic
The Properties Of Post-Starburst Quasars Based On Optical Spectroscopy, Sabrina L. Cales, Michael S. Brotherton, Zhaohui Shang, Jessie C. Runnoe, Michael A. Dipompeo, Vardha Nicola Bennert, Gabriela Canalizo, Kyle D. Hiner, R. Stoll, Rajib Ganguly, Aleksandar Diamond-Stanic
Physics
We present optical spectroscopy of a sample of 38 post-starburst quasars (PSQs) at z ~ 0.3, 29 of which have morphological classifications based on Hubble Space Telescope imaging. These broad-lined active galactic nuclei (AGNs) possess the spectral signatures of massive intermediate-aged stellar populations, making them potentially useful for studying connections between nuclear activity and host galaxy evolution. We model the spectra in order to determine the ages and masses of the host stellar populations, and the black hole masses and Eddington fractions of the AGNs. Our model components include an instantaneous starburst, a power law, and emission lines. We find …
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. Ii. Measuring Stellar Velocity Dispersion In Active Galaxies, Chelsea E. Harris, Vardha N. Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
A Local Baseline Of The Black Hole Mass Scaling Relations For Active Galaxies. Ii. Measuring Stellar Velocity Dispersion In Active Galaxies, Chelsea E. Harris, Vardha N. Bennert, Matthew W. Auger, Tommaso Treu, Jong-Hak Woo, Matthew A. Malkan
Physics
We derive spatially resolved stellar kinematics for a sample of 84 out of 104 observed local (0.02 < z < 0.09) galaxies hosting type-1 active galactic nuclei (AGNs), based on long-slit spectra obtained at the 10 m W. M. Keck-1 Telescope. In addition to providing central stellar velocity dispersions, we measure major axis rotation curves and velocity dispersion profiles using three separate wavelength regions, including the prominent Ca H&K, Mg Ib, and Ca II NIR stellar features. In this paper, we compare kinematic measurements of stellar velocity dispersion obtained for different apertures, wavelength regions, and signal-to-noise ratios, and provide recipes to cross-calibrate the measurements reducing systematic effects to the level of a few percent. We also provide simple recipes based on readily observable quantities such as global colors and Ca H&K equivalent width that will allow observers of high-redshift AGN hosts to increase the probability of obtaining reliable stellar kinematic measurements from unresolved spectra in the region surrounding the Ca H&K lines. In subsequent papers in this series, we will combine this unprecedented spectroscopic data set with surface photometry and black hole mass measurements to study in detail the scaling relations between host galaxy properties and black hole mass.