Collaborative Research: Raising the Bar: Radio Investigations of the Structure and Dynamics of the Galactic Bulge

研究人员将利用射电望远镜沿着银河系的平面寻找红巨星。这些恒星的显著特征是像超亮激光一样，由于在这种类型的恒星周围的环境中发现了一氧化硅分子（SiO），它们会发射无线电波。由于这种独特的特性，射电望远镜可以在很远的地方探测到这些恒星，即使它们隐藏在尘埃和气体云中。研究人员将利用这些恒星来研究我们星系的结构，并了解我们的星系是如何被其他邻近星系和银河系中的星团的引力所吸引的。通过寻找星系中恒星的不寻常运动，研究人员可以探测到过去矮星系与我们银河系的碰撞。研究人员将测试我们银河系中一个关键特征的模型，“条”，一个延伸到银河系中心两侧的线性结构。人们认为，这个棒状结构部分是由星团和气体的引力作用造成的。这些星团合并成为我们银河系的一部分。除了这个条形外，我们的银河系在中心附近也有一个“凸起”，在那里恒星到达高轨道。在银河系的我们这一区域，恒星集中在一个圆盘上。研究人员将为学生提供科学、技术、工程和数学（STEM）学科的参与机会和教育。这包括寻找少数民族学生参与项目，并着重加强女性的参与。通过这项研究奖励，研究生将得到培训，更多的本科生将有机会参加暑期研究工作。具体的科学目标包括星系凸起和中央星系盘的动力学和结构的建模。这些数据将允许定义条形体与银河系平面和中心人口的关系，以及凸起的强烈方形势对动力学的影响，以及“长”条形体的存在。特别是，n体模型和自洽模型将与恒星脉泽速度的直接动态测量结果进行比较。从近红外光谱可以确定星周包层的元素丰度和性质。研究者的研究对于理解所有螺旋星系的结构也很重要。银河系凸起提供了一个独特的实验室，因为它是唯一一个可以对许多盘状星系中发生的过程进行详细研究的地方。

The investigators will search for red giant stars along the plane of our Milky Way galaxy, using radio telescopes. These stars have the remarkable characteristic of acting like ultra-bright lasers, emitting radio waves due to the molecule Silicon Monoxide (SiO), which is found in the environment surrounding this type of star. Because of this unique feature, radio telescopes can detect these stars at great distances, even when they are hidden in clouds of dust and gas. The investigators will use the stars to study the structure of our galaxy and understand how our Galaxy is being pulled by the gravity of other nearby galaxies and clusters of stars in our Galaxy. By looking for unusual motions of stars in the galaxy, the investigators can detect the past collisions of dwarf galaxies with our Galaxy. The investigators will test models for a key feature seen in our Galaxy, "the bar", a linear structure extending on both sides of the center of our Galaxy. The bar is thought to partially result from the gravitational pull of clusters of stars and gas. These clusters merged to become part of our Milky Way. In addition to the bar, our Galaxy also shows a "bulge" near the center, where stars reach high orbits. In our region of the galaxy the stars are concentrated in a disk.The researchers will provide student participation opportunities and education within the science, technology, engineering and math (STEM) disciplines. This includes finding minority students to work on the project and concentrating on strengthening female participation. Through this research award, graduate students will be trained and additional undergraduate students will be have to opportunity for summer research jobs.Specific science goals include the modeling of the dynamics and the structure of the Galactic bulge and the central galactic disk. This data will allow defining the relationship of the bar to the populations of the Galactic plane and Center, and the effect of the strongly boxy potential of the bulge on dynamics, and the presence of a ``long'' bar. In particular, both N-body models and self-consistent models will be compared with direct dynamical measurements from the stellar maser velocities. From near-infrared spectra elemental abundances and properties of the circumstellar envelopes will be determined. The investigator's studies will also be important for understanding the structure of all spiral galaxies. The Galactic bulge provides a unique laboratory, as it is the only place where detailed studies are possible for the processes taking place in many disk galaxies.