TY - JOUR
T1 - Weak line quasars at high redshift
T2 - Extremely high accretion rates or anemic broad-line regions?
AU - Shemmer, Ohad
AU - Trakhtenbrot, Benny
AU - Anderson, Scott F.
AU - Brandt, W. N.
AU - Diamond-Stanic, Aleksandar M.
AU - Fan, Xiaohui
AU - Lira, Paulina
AU - Netzer, Hagai
AU - Plotkin, Richard M.
AU - Richards, Gordon T.
AU - Schneider, Donald P.
AU - Strauss, Michael A.
PY - 2010/10/20
Y1 - 2010/10/20
N2 - We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z = 3.55 and SDSS J123743.08+630144.9 at z = 3.49. In both sources, we detect an unusually weak broad Hβ line and place tight upper limits on the strengths of their [Oiii] lines. Virial, Hβ-based black hole mass determinations indicate normalized accretion rates of L/LEdd= 0 .4 for these sources, which is well within the range observed for typical quasars with similar luminosities and redshifts.We also present high-quality XMM-Newton imaging spectroscopy of SDSS J114153.34+021924.3 and find a hard-X-ray photon index of Γ = 1.91 -0.22+0.24, which supports the virial L/LEdd determination in this source. Our results suggest that theweakness of the broad emission lines inWLQsis not a consequence of an extreme continuum-emission source but instead due to abnormal broad emission line region properties.
AB - We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z = 3.55 and SDSS J123743.08+630144.9 at z = 3.49. In both sources, we detect an unusually weak broad Hβ line and place tight upper limits on the strengths of their [Oiii] lines. Virial, Hβ-based black hole mass determinations indicate normalized accretion rates of L/LEdd= 0 .4 for these sources, which is well within the range observed for typical quasars with similar luminosities and redshifts.We also present high-quality XMM-Newton imaging spectroscopy of SDSS J114153.34+021924.3 and find a hard-X-ray photon index of Γ = 1.91 -0.22+0.24, which supports the virial L/LEdd determination in this source. Our results suggest that theweakness of the broad emission lines inWLQsis not a consequence of an extreme continuum-emission source but instead due to abnormal broad emission line region properties.
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U2 - 10.1088/2041-8205/722/2/L152
DO - 10.1088/2041-8205/722/2/L152
M3 - Article
AN - SCOPUS:78649287921
SN - 2041-8205
VL - 722
SP - L152-L156
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2 PART 2
ER -