ACCRETION RATES OF RED QUASARS FROM THE HYDROGEN Pβ LINE

Journal Article · Sat Oct 10 00:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/812/1/66· OSTI ID:22525264

Kim, Dohyeong; Im, Myungshin ^[1]; Glikman, Eilat ^[2]; Woo, Jong-Hak ^[3]; Urrutia, Tanya ^[4]

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1. Center for the Exploration of the Origin of the Universe (CEOU), Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of)
2. Department of Physics, Middlebury College, Middlebury, VT 05753 (United States)
3. Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of)
4. Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, D-14482, Potsdam (Germany)

Red quasars are thought to be an intermediate population between merger-driven star-forming galaxies in dust-enshrouded phase and normal quasars. If so, they are expected to have high accretion ratios, but their intrinsic dust extinction hampers reliable determination of Eddington ratios. Here, we compare the accretion rates of 16 red quasars at z ∼ 0.7 to those of normal type 1 quasars at the same redshift range. The red quasars are selected by their red colors in optical through near-infrared (NIR) and radio detection. The accretion rates of the red quasars are derived from the Pβ line in NIR spectra, which is obtained by the SpeX on the Infrared Telescope Facility in order to avoid the effects of dust extinction. We find that the measured Eddington ratios (L{sub bol}/L{sub Edd} ≃ 0.69) of red quasars are significantly higher than those of normal type 1 quasars, which is consistent with a scenario in which red quasars are the intermediate population and the black holes of red quasars grow very rapidly during such a stage.

• OSTI ID: 22525264
• Journal Information: Astrophysical Journal, Vol. 812, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BLACK HOLES
COLOR
COMPARATIVE EVALUATIONS
COSMIC DUST
DETECTION
GALACTIC EVOLUTION
GALAXIES
HYDROGEN
INFRARED SPECTRA
NEAR INFRARED RADIATION
QUASARS
RED SHIFT
STAR EVOLUTION
STARS
TELESCOPES