The Space Density of High-Redshift QSOs in the Great Observatories Origins Deep Survey
The Space Density of High-Redshift QSOs in the Great Observatories Origins Deep Survey
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大天文台起源深巡中高红移 QSO 的空间密度
DOI：
10.1086/378788
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
E. Vanzella
中科院分区：
文献类型：
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作者：
S. Cristiani;D. Alexander;F. Bauer;W. Brandt;E. Chatzichristou;F. Fontanot;A. Grazian;A. Koekemoer;R. Lucas;P. Monaco;M. Nonino;P. Padovani;D. Stern;P. Tozzi;E. Treister;C. Urry;E. Vanzella
我们展示了在大天文台原点深度探测的320arcmin2区域内的17个高红移(3.5CCD5.2)类恒星对象(类恒星对象)的样本，该样本被选在22.45；z850和25.25等范围内，使用哈勃太空望远镜上的高级相机和钱德拉X射线天文台上的高级≲成像光谱仪进行深度成像。根据7个光谱红移和10个光度红移，我们估计最终样品将包含2到4个具有4<；z<；5.2的类星体。高红移中等光度(M145≃-23)类星体的缺乏是基于(1)根据斯隆数字巡天结果校准的纯光度演化而外推的z~2.7光度函数(Lf)，以及(2)暗物质晕中形成超大质量黑洞的恒定普遍效率。收集的证据支持在高红移时低频的密度演化，以及抑制低质量晕中SMBHs的形成或进食。
We present a sample of 17 high-redshift (3.5 ≲ z ≲ 5.2) quasi-stellar object (QSO) candidates in the 320 arcmin2 area of the Great Observatories Origins Deep Survey, selected in the magnitude range 22.45 < z850 < 25.25 using deep imaging with the Advanced Camera for Surveys on board the Hubble Space Telescope and the Advanced CCD Imaging Spectrometer on board the Chandra X-Ray Observatory. On the basis of seven spectroscopic and 10 photometric redshifts, we estimate that the final sample will contain between two and four QSOs with 4 < z < 5.2. A dearth of high-redshift moderate-luminosity (M145 ≃ -23) QSOs is observed with respect to predictions based on (1) the extrapolation of the z ~ 2.7 luminosity function (LF), according to a pure luminosity evolution calibrated by the results of the Sloan Digital Sky Survey, and (2) a constant universal efficiency in the formation of supermassive black holes (SMBHs) in dark matter halos. Evidence is gathered in favor of a density evolution of the LF at high redshift and of a suppression of the formation or feeding of SMBHs in low-mass halos.