Kavli Affiliate: Linhua Jiang
| First 5 Authors: Qian Yang, Paul J. Green, Xue-Bing Wu, Michael Eracleous, Linhua Jiang
| Summary:
"Changing-look quasars" (CLQs), discovered less than a decade ago, show
dramatic, rapid changes in optical/UV continuum and broad line emission. The
majority of CLQs have been found dimming as "turn-off" CLQs because most
selection methods start from samples of spectroscopically-confirmed quasars. We
present here a sample of 82 spectroscopically confirmed "turn-on" CLQs, 70 of
which are newly identified. The turn-on CLQs are selected from
spectroscopically classified galaxies with subsequent significant and dramatic
variability in both the optical and mid-infrared bands, indicating a mechanism
of changing accretion rate of the supermassive black holes rather than variable
obscuration. Based on their bright state Eddington ratios, turn-on CLQs are
associated with lower accretion rates compared to turn-off CLQs or typical SDSS
quasars with similar redshift and magnitude distributions, even though turn-on
CLQs have lower black hole masses. Most turn-on CLQs reside in host galaxies
that follow local relations between the central black hole mass and host galaxy
properties, such as stellar mass and velocity dispersion. However, their host
galaxies have higher mass than normal inactive galaxies, with star formation
rates more similar to hosts of Type 2 AGN than to the overall galaxy
population.
| Search Query: ArXiv Query: search_query=au:”Linhua Jiang”&id_list=&start=0&max_results=3