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

这个项目将利用光的引力弯曲来观察一个非常遥远的星系，其图像正在被前景中的一组星系团的引力放大。通过仔细研究遥远星系的放大率，他们将了解前景星系团中的质量分布。这个星系是独一无二的，因为该星系中的一颗恒星已经放大到可以在数十亿光年以外的地方看到。通过观察这颗恒星的亮度变化，他们将了解前景星系团中的恒星质量。该项目还将为明尼苏达大学双子城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与透镜星系图像的表面亮度空间变化，以确定最准确的透镜星团质量分布图。通过使用大型双筒望远镜获得这颗高度放大的单个恒星的3年光曲线，他们将能够测量微透镜光波动，这可以用来限制前景星团中星系团内恒星的质量函数。这将有助于对最初的大众功能施加限制。这一奖项反映了NSF的法定使命，并已通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.