Probing galaxies with quasar absorption lines

遥远的类星体（有时也被称为qso）可以作为宇宙边缘的灯塔，用来研究位于它们和地球之间的星系。我的研究重点是利用介入星系在类星体光谱上的印记来研究类星体的形成和演化。虽然这个技术已经有几十年的历史了，但我的研究正在寻找这个想法的新应用。例如，我的团队已经完善了一种技术，可以发现罕见的情况，即背景QSO探测介入星系的高度富含金属的区域。预计这些视线中还会含有丰富的分子，我们可以用这些分子来模拟星系的物理特征，甚至可以追踪基本常数随时间的演变。在非常极端的情况下，我们甚至可以看到有机化合物的特征，我们最近首次在宇宙距离上探测到这种特征。

Distant quasars (also sometimes called QSOs) can be used as lighthouses at the edge of the universe to study galaxies that lie between them and the Earth. My research focuses on using the imprints of intervening galaxies on the spectra of quasars to study their formation and evolution. Whilst this technique is several decades old, my research is finding novel applications of the idea. For example, my team has perfected a technique for finding rare cases where the background QSO probes highly metal-enriched regions of an intervening galaxy. These sight lines are also expected to be rich in molecules which we can use to model the physical characteristics of the galaxy and even trace evolution of fundamental constants with time. In very extreme cases, we can even see the signatures of organic compounds and we have recently made the first detection of such features at cosmological distances.