Studies of Star Formation with Galactic Plane Surveys

该计划通过利用最近的银河平面调查的丰富协同作用来研究星星的形成过程，这些调查跟踪星际气体和尘埃的各种阶段和条件。主要的重点是综合这些集体调查数据集内的信息，以提供最完整的观测约束的物理学的星星形成在银河系的内盘。特别地，研究了在一个巨大的分子云中负责发展大质量团块的物理过程，这些团块是星团和OB星凝聚的。（五所大学射电天文台）12 CO和13 CO发射调查、Bolocam银道面调查（BGPS）、甚大阵（VLA）银道面调查、和斯皮策遗产计划多波段成像光度计斯皮策内银河平面调查（MIPSGAL）。通过将毫米波、尘埃和射电连续谱测量中确定的源与13 CO发射速度联系起来，可以测量银河系中不同环境和位置的巨大分子云内的星星形成活动。这些措施包括云质量的部分居住在大规模的团块，来自红外光度的星星形成率，和一个普查莱曼α连续光子从无线电光度。这些性质进行了比较的动力学状态和速度结构的母体分子云来自13 CO的排放。这些信息被用来评估星际湍流和膨胀电离锋驱动的激波在调节星星形成中的作用。这个项目的一部分是校准一组云的尺寸-速度色散关系的系数，这些云的距离通过三角视差测量被确定为优于10%。这种校准为银河系中的巨型分子云建立了一种新的距离测量方法，它可以补充或改进从银河系自转曲线导出的运动学距离，在银河系中建立一种新的距离测量方法，这对研究银河系结构和调查单个星星形成区域具有重要意义。 在项目期间，在网上提供了一份星星形成区的汇编。这些数据集的多波长、多维特性要求开发和使用可适用于其他天文数据的广义多变量方法。该项目是博士论文的基础;它将使受资助的研究生充分参与，从而有助于培养下一代科学家。

This program investigates the star formation process by exploiting the rich synergy of recent Galactic Plane Surveys that trace various phases and conditions of interstellar gas and dust. The main focus is to synthesize the information resident within these collective survey data sets to provide the most complete observational constraints to the physics of star formation in the inner disk of the Galaxy. In particular, physical processes within a giant molecular cloud responsible for the development of massive clumps from which clusters and OB stars condense are investigated.The data sets include the FCRAO (Five College Radio Astronomy Observatory) surveys of 12CO and 13CO emission, the Bolocam Galactic Plane Survey (BGPS), the Very Large Array (VLA) Galactic Plane Survey, and the Spitzer Legacy program Multiband Imaging Photometer for Spitzer Inner Galactic Plane Survey (MIPSGAL). By linking sources identified within the millimeter, dust, and radio continuum surveys to velocities of 13CO emission, one obtains measures of the star formation activity within giant molecular clouds over varying environments and locations in the Galaxy. Such measures include the fraction of cloud mass residing within massive clumps, star formation rates derived from infrared luminosity, and a census of Lyman-alpha continuum photons from the radio luminosity. These properties are compared to the dynamical state and velocity structure of the parent molecular cloud derived from 13CO emission. This collective information is used to evaluate the role of shocks driven by interstellar turbulence and expanding ionization fronts on regulating star formation.Part of this project is to calibrate the coefficient of the size-velocity dispersion relationship for a set of clouds whose distances have been determined to better than 10% by trigonometric parallax measurements. This calibration then establishes a new distance measure for giant molecular clouds in the Milky Way that can complement or improve upon kinematic distances derived from the Galactic rotation curve.The establishment of a new distance measure in the Galaxy significantly aids studies of Galactic structure and investigations of individual star forming regions. A compilation of star forming regions is made available on the web during the project. The multi-wavelength, multi-dimensional character of these data sets requires the development and use of generalized multi-variate methods that could be applied to other astronomical data. This project is the basis of a doctoral thesis; it will fully engage the funded graduate student and therefore contribute to the training of the next generation of scientists.