Low Mass Galaxies and the Baryonic Tully Fisher Relation as a Distance Indicator

除非知道天体的距离，否则很难理解它。 这就是为什么距离估计器如此珍贵。 标度关系可以用来推断星系的距离。 重子塔利·费舍尔关系（BTFR）将星系的自旋速度与其气体和恒星的总质量联系起来。 天文学家们刚刚开始询问低质量星系是否遵循BTFR。 这些星系散布在整个本地宇宙中，知道它们的距离可以打开新的调查路线。 该团队将使用NSF的阿雷西博天文台的观测数据来测量低质量星系的气体含量，旋转速度和衰退速度。 他们将计算重子的总质量，看看星系是否服从BTFR。 如果是这样，他们将获得双鱼座-英仙座超星系团（PPS）附近和内部的星系距离。 他们将比较新的距离和衰退速度与模拟，以了解PSS是如何形成的。 高级团队成员将培训初级团队成员。 康奈尔大学的研究小组将继续参与“本科生阿尔法研究小组”的计划，从而使19所主要本科院校的学生参与这项研究。该研究小组将调查低质量、高密度星系的数量。 他们的目标是（1）建立一个强大的BTFR本地恒星形成盘星系，（2）使用BTFR作为距离估计和探测制度，重子不足成为重要的，和（3）推断BTFR的双鱼座-英仙座超星系团（PPS）和它的前景和背景空洞的距离，以限制PPS形成的模拟。

It is difficult to understand an astronomical object unless its distance is known. That is why distance estimators are so precious. Scaling relations can be used to infer the distance to a galaxy. The Baryonic Tully Fisher Relation (BTFR) links the spin speed of a galaxy to its total mass in gas and stars. Astronomers are just beginning to ask if low mass galaxies obey the BTFR. These galaxies are sprinkled throughout the local universe and knowing their distances can open novel lines of inquiry. The team will use observations from NSF's Arecibo Observatory to measure the gas content, spin speed and recession speed of low mass galaxies. They will tally up the total masses in baryons to see if the galaxies obey the BTFR. If so, they will derive distances to galaxies near and inside the Pisces-Perseus Supercluster (PPS). They will compare the new distances and recession speeds to simulations to understand how the PSS formed. Senior team members will train junior team members. The Cornell team will continue to participate in the Undergraduate ALFALFA Team initiative, thereby involving students at 19 primarily undergraduate institutions in the research.The team will investigate the population of low-mass, HI-rich galaxies. Their goals are to (1) establish a robust BTFR for local star-forming disk galaxies, (2) use the BTFR as a distance estimator and to probe regimes where baryon deficiency becomes important, and (3) infer BTFR distances in the Pisces-Perseus Supercluster (PPS) and its foreground and background voids, to constrain simulations of PPS formation.