The Intracluster Mass Function from Brown Dwarfs to Stellar-Mass Black Holes from the Microlensing Fluctuations of an Extremely Magnified Star

该项目将利用光的引力弯曲来观察一个非常遥远的星系，其图像被前景中星系团的引力放大。通过仔细研究遥远星系的放大率，他们将了解前景星系团的质量分布。这个星系是独一无二的，因为该星系中的一颗星星被放大到足以在数十亿光年的距离被看到。通过观察这颗星星亮度的变化，他们将了解前景星系团中恒星的质量。该项目还将为明尼苏达大学双城分校的贝尔博物馆开发几个展品，该项目将比较不同的透镜质量模型和透镜星系图像的表面亮度空间变化，以确定透镜星系团最准确的质量分布图。通过使用大型双筒望远镜获得单个高度放大的星星的3年光变曲线，他们将能够测量微透镜光波动，这些微透镜光波动可用于限制前景星团中星团内恒星的质量函数。这个奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

This project will take advantage of the gravitational bending of light to observe a very distant galaxy whose image is being magnified by the gravity of a cluster of galaxies in the foreground. By carefully studying the magnification of the distant galaxy they will learn about the mass distribution in the foreground cluster. This galaxy is unique because one star in that galaxy has been magnified enough to be seen at a distance of billions of lightyears. By observing changes in brightness of this star, they will learn about the masses of stars in the foreground cluster of galaxies. The project will also develop several exhibits for he Bell Museum at the University of Minnesota-Twin Cities.The project will compare different lens mass models with the surface brightness spatial variations across the lensed galaxy images to determine the most accurate mass distribution map of the lensing cluster. By obtaining a 3-year light curve for the single, highly magnified star, using the Large Binocular Telescope, they will be able to measure microlensing light fluctuations that can be used to constrain the mass function of the intracluster stars in the foreground cluster. This will help place constraints on the initial mass function.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.