Gamma-ray Burst Afterglows as a New Probe of the Young Universe

Lyman-alpha吸收器（DLAs），传统上沿着背景类星体的视线被发现，探测类似于附近发光星系盘的中性气体区域，也就是说，它们是在高红移时促进恒星形成的气藏。然而，由于类星体比前景中微弱的星系更亮，识别DLA的恒星对口是困难的，因此了解DLA星系的本质需要一种新的方法。这个项目将沿着伽马射线爆发（GRB）余辉的视线识别一个新的dla样本，其亮度使它们成为介入气体的敏感探测器，但一旦余辉消退，它们就不会干扰对吸收星系的研究。GRB余辉的早期、高分辨率光谱以及沿着视线的深度、后期成像和光谱调查为研究DLA星系及其星际介质提供了一种新的方法。所获得的数据将存档并提供给社会，并将对广泛的科学研究有用。这项工作将通过参与观察和短期课程来教育研究生，并激励本科生和其他年轻科学家。通过与阿德勒天文馆的合作，精致的成像和光谱数据将与计算机模拟相结合，为公众教育制作动画和海报。

AST-0607510ChenDamped Lyman-alpha absorbers (DLAs), traditionally found along the sightlines toward background quasars, probe neutral gas regions that resemble the disks of nearby luminous galaxies, that is, they are the gas reservoir that fosters star formation at high redshift. However, identifying the stellar counterpart of the DLAs is difficult because the quasars outshine the faint galaxies in the foreground, so understanding the nature of DLA galaxies requires a new approach. This program will identify a new sample of DLAs along the sightlines toward gamma-ray burst (GRB) afterglows, whose brightness makes them a sensitive probe of intervening gas, but which do not interfere with studies of absorbing galaxies once the afterglow has faded. Early-time, high-resolution spectroscopy of GRB afterglows together with deep, late-time imaging and spectroscopic surveys along the sightlines offers a novel way to study the DLA galaxies and their interstellar medium.Data obtained will be archived and made available to the community, and will be useful for a broad range of scientific studies. The work will educate a graduate student, and inspire undergraduates and other young scientists, through participation in observations and short courses. Exquisite imaging and spectroscopic data will be combined with computer simulations to produce animations and posters for public education, through collaboration with the Adler Planetarium.