Modelling Integrated Spectra of Globular Clusters in M31 andthe Galaxy

球状星团是研究得很好的系统，因为它们提供了观察大量不同质量的恒星的机会，这些恒星的年龄和初始化学成分几乎相同。我们对恒星演化的大部分知识都来自于对这些系统的研究。然而，到目前为止，我们只能真正观察到非常近的物体中的单个恒星，那些与我们自己的星系或麦哲伦星云有关的恒星。这个计划是为了使我们能够获得更遥远的球状星团的化学成分和年龄的准确信息。研究人员结合了国际公认的恒星大气理论、光谱学和球状星团研究领域的专业知识。他们将利用模型恒星大气的计算，恒星演化计算，以及各种光度函数和年龄来预测可以测量的遥远天体的综合光谱。他们将用来自附近球状星团的数据来校准他们的模型参数，这些参数是通过其他方式确定的。

Globular clusters are well studied systems, because they offer the opportunity to look on a large number of stars of different masses, all with pretty much the same age and initial chemical composition. Much of our knowledge of stellar evolution comes from the study of these systems. However, we can, as yet only really look at individual stars in very nearby objects, those associated with our own galaxy, or with the Magellanic Clouds. This program is an attempt to enable us to obtain accurate information about the chemical composition and age of much more distant globular clusters. The investigators combine internationally recognized expertise in the fields of the theory of stellar atmospheres, spectroscopy and the study of globular clusters. They will utilize computation of model stellar atmospheres, stellar evolution calculations, and various luminosity functions and ages to predict integrated spectra which can be measured for distant objects. They will calibrate their model parameters with data from nearby globular clusters for which these parameters have been determined by other means.