Walter Fabian, Bertoldi Frank, Carilli Chris, Cox Pierre, Lo K Y, Neri Roberto, Fan Xiaohui, Omont Alain, Strauss Michael A, Menten Karl M
National Radio Astronomy Observatory, PO Box 0, Socorro, New Mexico 87801, USA.
Nature. 2003 Jul 24;424(6947):406-8. doi: 10.1038/nature01821.
Observations of molecular hydrogen in quasar host galaxies at high redshifts provide fundamental constraints on galaxy evolution, because it is out of this molecular gas that stars form. Molecular hydrogen is traced by emission from the carbon monoxide molecule, CO; cold H2 itself is generally not observable. Carbon monoxide has been detected in about ten quasar host galaxies with redshifts z > 2; the record-holder is at z = 4.69 (refs 1-3). Here we report CO emission from the quasar SDSS J114816.64 + 525150.3 (refs 5, 6) at z = 6.42. At that redshift, the Universe was only 1/16 of its present age, and the era of cosmic reionization was just ending. The presence of about 2 x 1010 M\circ of H2 in an object at this time demonstrates that molecular gas enriched with heavy elements can be generated rapidly in the youngest galaxies.
对高红移类星体宿主星系中分子氢的观测为星系演化提供了基本限制，因为恒星正是由这种分子气体形成的。一氧化碳分子（CO）的发射可追踪分子氢；冷的H₂本身通常无法观测到。在约十个红移z > 2的类星体宿主星系中已探测到一氧化碳；记录保持者的红移为z = 4.69（参考文献1 - 3）。在此，我们报告了红移z = 6.42的类星体SDSS J114816.64 + 525150.3（参考文献5、6）的CO发射。在该红移下，宇宙年龄仅为当前年龄的1/16，宇宙再电离时代刚刚结束。此时一个天体中存在约2×10¹⁰ M⊙的H₂，这表明在最年轻的星系中富含重元素的分子气体能够快速生成。
