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Host Galaxies of Lensed Luminous Quasars at z~2

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 نشر من قبل Hans-Walter Rix
 تاريخ النشر 1999
  مجال البحث فيزياء
والبحث باللغة English
 تأليف H.-W. Rix




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We present H-band observations of gravitationally lensed QSO host galaxies obtained with NICMOS on HST as part of the CfA-Arizona-Gravitational-Lens-Survey (CASTLES). The detections are greatly facilitated by the lensing magnification in these systems; we find that most hosts of radio-quiet QSOs (RQQ) at z~2 are of modest luminosity (L<L_*). They are 2-5 times fainter than the hosts of radio-loud QSOs at the same epoch. Compared to low redshifts, RQQ hosts at z~2 also support higher nuclear luminosities at given stellar host mass. This suggests that the supermassive black holes at their centers grew faster at early epochs than the stellar body of their surrounding host galaxies.



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