A new estimation of HD/2H2 at high redshift using the spectrum of the quasar J 2123-0050
[摘要] We present a new analysis of the quasar spectrum J 2123-0050 obtained using VLT/UVES. The H2/HD absorption system at z = 2.059 was analysed. This system consists of two subsystems with zA= 2.05933 and zB= 2.05955. The HD lines have been detected only in subsystem A with the column density of log N = 13.87 ± 0.06. We have determined the column density of H2in this subsystem, log N = 17.93 ± 0.01, which is about three times larger than estimation derived early from analyses of quasar spectrum obtained using KECK/HIRES [1]. The derived ratio HD/2H2= (4.28 ± 0.60) × 10-5is the largest in quasar spectra, nevertheless it coincides with the primordial deuterium abundance within 2σ error. Additionally, we have found some evidence in the partial covering effect for the H2system.
[发布日期] [发布机构] Ioffe Institute, Polytekhnicheskaya 26, Saint-Petersburg; 194021, Russia^1;Peter the Great St.-Petersburg Polytechnic University, Polytekhnicheskaya 29, Saint-Petersburg; 195251, Russia^2
[效力级别] 天文学 [学科分类] 天文学(综合)
[关键词] Absorption system;Column density;High-redshift;Quasar spectra [时效性]