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arXiv · astro-ph/0606493

Discovery of a new high redshift QSO at z=5.96 with the Subaru telescope

Abstract

We report a discovery of a new high redshift quasar at $z=5.96$, observed with the FOCAS long-slit spectrograph on board the Subaru telescope. The spectrum shows strong and broad Ly$α$+NV emission lines with a sharp discontinuity to the blue side. A Ly$β$+OVI emission line is also detected, providing a consistent redshift measurement with the Ly$α$+NV emission. The QSO has an absolute magnitude of $M_{AB,1450}=-26.9$ ($H_{0}=50$km s$^{-1}$ Mpc$^{-1}$, $q_0=0.5$). The spectrum shows significant flux in the region 8000-8300 $Å$ and thus does not show a complete Gunn-Peterson trough in the redshift range 5.58 to 5.82, along the line of sight to this $z=5.96$ QSO. Therefore the Universe was already highly ionized at $z=5.82$

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Tomotsugu Goto. 2006-06-20. Discovery of a new high redshift QSO at z=5.96 with the Subaru telescope. https://doi.org/10.1111/j.1365-2966.2006.10702.x

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