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No excess of bright galaxies around the redshift 7.1 quasar ULAS J1120+0641

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 نشر من قبل Chris Simpson
 تاريخ النشر 2014
  مجال البحث فيزياء
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We present optical and near-infrared imaging of the field of the z=7.0842 quasar ULAS J112001.48+064124.3 taken with the Hubble Space Telescope. We use these data to search for galaxies that may be physically associated with the quasar, using the Lyman break technique, and find three such objects, although the detection of one in Spitzer Space Telescope imaging strongly suggests it lies at z~2. This is consistent with the field luminosity function and indicates that there is no excess of >L* galaxies within 1 Mpc of the quasar. A detection of the quasar shortward of the Ly-alpha line is consistent with the previously observed evolution of the intergalactic medium at z>5.5.



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259 - James S. Bolton 2011
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