TY - JOUR
T1 - The Hunt for Red Quasars
T2 - Luminous Obscured Black Hole Growth Unveiled in the Stripe 82 X-Ray Survey
AU - Lamassa, Stephanie M.
AU - Glikman, Eilat
AU - Brusa, Marcella
AU - Rigby, Jane R.
AU - Ananna, Tonima Tasnim
AU - Stern, Daniel
AU - Lira, Paulina
AU - Urry, C. Megan
AU - Salvato, Mara
AU - Alexandroff, Rachael
AU - Allevato, Viola
AU - Cardamone, Carolin
AU - Civano, Francesca
AU - Coppi, Paolo
AU - Farrah, Duncan
AU - Komossa, S.
AU - Lanzuisi, Giorgio
AU - Marchesi, Stefano
AU - Richards, Gordon
AU - Trakhtenbrot, Benny
AU - Treister, Ezequiel
N1 - Publisher Copyright: © 2017. The American Astronomical Society. All rights reserved.
PY - 2017/10/1
Y1 - 2017/10/1
N2 - We present results of a ground-based near-infrared campaign with Palomar TripleSpec, Keck NIRSPEC, and Gemini GNIRS to target two samples of reddened active galactic nucleus (AGN) candidates from the 31 deg2 Stripe 82 X-ray survey. One sample, which is ∼89% complete to K < 16 (Vega), consists of eight confirmed AGNs, four of which were identified with our follow-up program, and is selected to have red R - K colors (>4, Vega). The fainter sample (K > 17, Vega) represents a pilot program to follow-up four sources from a parent sample of 34 that are not detected in the single-epoch SDSS catalog and have WISE quasar colors. All 12 sources are broad-line AGNs (at least one permitted emission line has an FWHM exceeding 1300 km s-1) and span a redshift range 0.59 < z < 2.5. Half the (R - K)-selected AGNs have features in their spectra suggestive of outflows. When comparing these sources to a matched sample of blue Type 1 AGNs, we find that the reddened AGNs are more distant (z > 0.5), and a greater percentage have high X-ray luminosities (LX,full > 1044 erg s-1). Such outflows and high luminosities may be consistent with the paradigm that reddened broad-line AGNs represent a transitory phase in AGN evolution as described by the major merger model for black hole growth. Results from our pilot program demonstrate proof of concept that our selection technique is successful in discovering reddened quasars at z > 1 missed by optical surveys.
AB - We present results of a ground-based near-infrared campaign with Palomar TripleSpec, Keck NIRSPEC, and Gemini GNIRS to target two samples of reddened active galactic nucleus (AGN) candidates from the 31 deg2 Stripe 82 X-ray survey. One sample, which is ∼89% complete to K < 16 (Vega), consists of eight confirmed AGNs, four of which were identified with our follow-up program, and is selected to have red R - K colors (>4, Vega). The fainter sample (K > 17, Vega) represents a pilot program to follow-up four sources from a parent sample of 34 that are not detected in the single-epoch SDSS catalog and have WISE quasar colors. All 12 sources are broad-line AGNs (at least one permitted emission line has an FWHM exceeding 1300 km s-1) and span a redshift range 0.59 < z < 2.5. Half the (R - K)-selected AGNs have features in their spectra suggestive of outflows. When comparing these sources to a matched sample of blue Type 1 AGNs, we find that the reddened AGNs are more distant (z > 0.5), and a greater percentage have high X-ray luminosities (LX,full > 1044 erg s-1). Such outflows and high luminosities may be consistent with the paradigm that reddened broad-line AGNs represent a transitory phase in AGN evolution as described by the major merger model for black hole growth. Results from our pilot program demonstrate proof of concept that our selection technique is successful in discovering reddened quasars at z > 1 missed by optical surveys.
KW - X-rays: galaxies
KW - galaxies: active
KW - infrared: galaxies
KW - quasars: general
KW - quasars: supermassive black holes
UR - http://www.scopus.com/inward/record.url?scp=85031113290&partnerID=8YFLogxK
U2 - https://doi.org/10.3847/1538-4357/aa87b5
DO - https://doi.org/10.3847/1538-4357/aa87b5
M3 - مقالة
SN - 0004-637X
VL - 847
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 100
ER -