Probing galaxies with quasar absorption lines

遥远的类星体(有时也称为类星体)可以被用作宇宙边缘的灯塔，以研究位于它们和地球之间的星系。我的研究重点是利用类星体光谱上的中间星系印记来研究它们的形成和演化。虽然这项技术已经有几十年的历史了，但我的研究正在发现这一想法的新应用。例如，我的团队已经完善了一种寻找罕见情况的技术，在这种情况下，背景类星体探测到了介于其中的星系中金属高度丰富的区域。这些视线还有望含有丰富的分子，我们可以用它们来模拟银河系的物理特征，甚至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，最近我们在宇宙距离处首次探测到了这种特征。

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.