Collaborative Research: Unveiling Dark Matter in Dwarf Spheroidal Galaxies

尽管暗物质（DM）遍布整个宇宙，但它在今天仍然像它的引力特征第一次被注意到时一样难以捉摸。幸运的是，矮星系继续提供一个独特的窗口，以了解DM的本质，因为它们是已知最小的DM结构的宿主，可能代表着巨大的原始人口的幸存者。不幸的是，矮星系的研究依赖于观察单个恒星的运动，并通过模型来解释它们，这是有缺陷的，因为任何一个星系的样本都很小，而且需要高度限制性的假设来获得答案。现在有可能在附近的矮球状星系中获得数千颗恒星的样本，而以前通常只有几十颗恒星。与此同时，新的、复杂得多的非参数统计技术正在发展，它不仅包括对一些标准动力学假设的检验，而且可能提供一些方法来放松这些假设。本研究的最终目标是在所有邻近的矮球状星系中，以尽可能少的假设面对最大数量的离散速度，建立一个运动学模型。天文学家和统计学家之间的密切合作将两所大学的研究人员联系在一起，包括可以继续这种合作传统的学生，并通过提供新设备和广泛可用的数据和统计方法为整个天文学界服务。研究结果将用于公共和K-5的宣传，这已经是每个研究人员活动的常规部分。

AST-0507511OlszewskiThough it permeates the entire Universe, dark matter (DM) remains as elusive today as when its gravitational signature was first noted. Fortunately, dwarf galaxies continue to offer a unique window into the nature of DM, as they are host to the smallest known DM structures and may represent the survivors of a vast primordial population. Unfortunately, dwarf galaxy studies rely on observing the motions of individual stars and their interpretation by models, and this is flawed both by having only small samples for any one galaxy, and by requiring highly restrictive assumptions to obtain an answer. It is now possible to obtain samples of thousands of stars in nearby dwarf spheroidal galaxies, where it was previously usual to have only tens of stars. At the same time, new, far more sophisticated non-parametric statistical techniques are being developed, which not only include tests of some of the standard dynamical assumptions, but also may offer ways to relax some of those assumptions. The ultimate goal of this research is a kinematical model with the fewest possible assumptions being confronted with the maximum number of discrete velocities in all of the nearby dwarf spheroidal galaxies.This close collaboration between astronomers and statisticians links researchers at two universities, including students who can continue this collaborative tradition, and serves the entire astronomical community through the provision of new equipment and the widespread availability of the data and the statistical methods. The results will feed into public and K-5 outreach, which are already a regular part of each researcher's activities.