Observational Studies of High Redshift Quasars

类星体的红移截止将通过 对高红移类星体的系统观测。 已知的是 给定光度的类星体的数量随着 增加红移。 然而，超过2.5或3的红移， 类星体的数量会减少 这种现象可能 标志着类星体在宇宙中的第一次出现，大约2 宇宙大爆炸后的十亿年 目前， 在高红移的类星体数量很少被记录。 这些 类星体非常罕见。 通常一个高红移类星体是 在天空中的10,000颗恒星中发现。 调查技术将 涉及视频记录的低色散光谱， 用200英寸的望远镜观测了大约100万个微弱的天体 在帕洛玛 显示发射线的物体将是 选定. 所有发射线物体的后续光谱学 将显示哪些物体是类星体， 它们的红移 通过仔细控制和校准 调查，将有可能评估其完整性限制， 从而对高红移类星体进行定量普查。 结果将允许不同的假设进行评估 提出解释类星体的突然出现在早期 宇宙 这种现象很可能与出生有关。 银河系。

The redshift cutoff of quasars will be studied by carrying out systematic surveys for high-redshift quasars. It is known that the number of quasars of given luminosity increases with increasing redshift. Beyond a redshift of 2.5 or 3, however, there is a drop in quasar numbers. This phenomenon probably signifies the first appearance of quasars in the universe, about 2 billion years after the Big Bang. At the present time the drop in quasar numbers at high redshift is poorly documented. These quasars are very rare. Typically one high-redshift quasar is found among 10,000 stars in the sky. The survey technique will involve video recording the low-dispersion spectra of approximately 1 million faint objects with the 200-inch telescope at Palomar. The objects that show emission lines will be selected. Follow-up spectroscopy of all the emission-line objects will show which of these objects are quasars as well as measure their redshifts. By careful control and calibration of the survey, it will be possible to evaluate its completeness limits, and thus conduct a quantitative census of high-redshift quasars. The results will allow the evaluation of different hypotheses proposed to explain the sudden appearance of quasars in the early universe. This phenomenon may well be associated with the birth of galaxies.