Ohta K, Yamada T, Nakanishi K, Kohno K, Akiyama M, Kawabe R
Department of Astronomy, Kyoto University, Japan.
Nature. 1996 Aug 1;382(6590):426-8. doi: 10.1038/382426a0.
Although great efforts have been made to locate molecular gas--the material out of which stars form--in the early Universe, there have been only two firm detections at high redshift. Both are gravitationally lensed objects at redshift z approximately = 2.5 (refs 9-14). Here we report the detection of CO emission from the radio-quiet quasar BR1202 - 0725, which is at redshift z = 4.69. From the observed CO luminosity, we estimate that almost 10(11) solar masses of molecular hydrogen are associated with the quasar; this is comparable to the stellar mass of a present-day luminous galaxy. Our results suggest that BR1202 - 0725 is a massive galaxy, in which the gas is largely concentrated in the central region, and that is currently undergoing a large burst of star formation.
尽管人们付出了巨大努力在早期宇宙中寻找分子气体——恒星形成的物质，但在高红移处仅有两次确凿的探测。这两个都是红移约为z = 2.5的引力透镜天体（参考文献9 - 14）。在此我们报告对射电宁静类星体BR1202 - 0725的一氧化碳（CO）发射的探测，其红移为z = 4.69。根据观测到的CO光度，我们估计与该类星体相关的分子氢质量几乎为10¹¹个太阳质量；这与一个当前发光星系的恒星质量相当。我们的结果表明，BR1202 - 0725是一个大质量星系，其中气体主要集中在中心区域，并且目前正在经历一次大规模的恒星形成爆发。
