The formation and evolution of massive galaxies

观测宇宙学是试图了解当今宇宙丰富而复杂的结构形成和演化的过程。虽然结构形成的概括性现在已经确立，但星系演化的细节仍然不清楚，这主要是因为在小范围内表现出的复杂物理。我在这一领域的研究方法是多方面的，结合了许多不同但互补的研究。我致力于对少数星系的详细研究，这可以教给我们推动它们演化的非常具体的物理原理；也可以对大样本进行统计研究，提供关于星系的全球属性和星系演化的整体趋势的信息。研究孤立存在的星系以及在独特的高密度区域演化的星系限制了环境在形成星系中的作用，这是我们知道的一个重要因素。我还对整个电磁光谱进行了采样，尽管重点放在近红外波长制度上，到目前为止，对这一制度的研究相对较少。这样的多波长数据至关重要，因为不同波长的观测探测到了与星系演化相关的不同物理过程。例如，红外线允许我们研究星系中当前的恒星形成，而光学则给我们提供关于以前恒星形成的信息。我对这样的问题感兴趣：环境是如何驱动星系进化的？大质量星系是在恒星形成的一次爆发中形成的，还是它们的增长随着时间的推移而延长？一个不断增长的中央黑洞是否调节了星系形成恒星的能力？如果是，又是如何调节的？使用上述补充技术，以及新一代望远镜和探测器，我们现在可以开始回答这些问题。

Observational cosmology is an attempt to understand the processes by which the rich and complex structure in the present-day universe formed and evolved. While the generalities of structure formation are now well established, the details of galaxy evolution remain unclear, largely due to the complex physics which manifests on small scales.  My approach to research in this area is multifacited, combining a number of different, yet complementary, studies. I work on detailed studies of small numbers of galaxies, which can teach us about very specific physics driving their evolution; but also statistical studies of large samples, which provides information on global properties of galaxies and the overall trends in galaxy evolution. Studying galaxies which exist in isolation as well as those evolving in unique high density regions constrains the role of the environment in forming galaxies, which we know to be an important factor. I also sample the entire electromagnetic spectrum, though with a strong focus on the  infrared wavelength regime, which until now has been relatively poorly studied. Such multiwavelength data are crucial as observations at different wavelengths probe different physical processes which are relevant to galaxy evolution. For example, the infrared allows us to study the current star formation in a galaxy, while optical light gives us information on previous star formation. I am interested in questions such as: how does the environment drive galaxy evolution?  Do massive galaxies form in a single burst of star formation or is their growth extended over time? Does a growing central black hole regulate the the ability of a galaxy to form stars, and if so, how? Using the complementary techniques described above, and the new generation of telescopes and detectors, we can now begin to answer these questions.