RAVE: Galactic Evolution from the Radial Velocity Experiment

该奖项由2009年美国复苏和再投资法案(公法111-5)资助。怀斯博士将利用径向速度实验(RAVE)的恒星光谱，研究银河系薄盘演化的早期阶段和厚盘的形成。这项调查使用1.2米英国施密特望远镜上的光纤馈电光谱仪，一次获得150颗恒星的光谱。从这些数据中，她将测量恒星朝向或远离我们的运动，并估计其表面重力和温度、化学丰度和恒星自转。每年都会有一名研究生前往澳大利亚，为狂欢做观察。一名学生将研究一个可能代表银河系盘状恒星的样本；这些恒星将从RAVE中挑选出来，金属丰度较低(低于太阳值的十分之一)，但遵循盘状恒星的近圆形轨道特征。为了获得更精确的化学丰度，将采用高分辨率光谱。第二个学生将使用元素丰度的详细模式来测试这些恒星是否可能是在被银河系吞噬的卫星星系中诞生的，并开发一个早期盘形成的模型。这个奖项将支持两名研究生。RAVE数据库将成为天文学界广泛有用的资源。该合作将以符合虚拟天文台标准的形式发布其数据库，使社区能够访问该数据库。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Dr Wyse will investigate the early phases of evolution of the Milky Way's thin disk and the formation of its thick disk by using stellar spectra from the Radial Velocity Experiment (RAVE). This survey uses a fiber-fed spectrograph on the 1.2-meter UK Schmidt Telescope to obtain spectra of 150 stars at a time. From these, she will measure the star's motion towards or away from us, and estimate its surface gravity and temperature, chemical abundances and stellar rotation. A graduate student will travel each year to Australia to make observations for RAVE. One student will study a sample that may represent the first stars in the Milky Way's disk; they will be selected from RAVE to have a low metal abundance (below one-tenth of the Sun's value), but to follow the near-circular orbits characteristic of disk stars. High-resolution spectra will be taken to obtain more precise chemical abundances. A second student will use the detailed pattern of element abundances to test whether these stars could have been born in satellite galaxies that were swallowed by the Milky Way, and to develop a model for early disk formation.This award will support two graduate students. The RAVE database will be a widely useful resource across the astronomical community. The collaboration will release its database in a form that is compliant with the standards of the Virtual Astronomical Observatory, making it accessible to the community.