Collaborative Proposal: Through the Gas Darkly: Birth and Death in the Milky Way

银河系中大多数恒星的诞生和死亡都是在光学望远镜的视野中发生的。厘米级的无线电波和强x射线可以穿透遮蔽我们视线的气体和尘埃，但由于先前所有搜索的角度分辨率和灵敏度有限，我们只能透过黑暗的气体进行观察，试图对银河系的恒星形成和消亡进行普查。Drs。哥伦比亚大学的David Helfand和加州大学戴维斯分校的Robert Becker将使用甚大阵列（VLA）对银河面进行新的调查，并进行广泛的光学和近红外后续观测，以补充xmm -牛顿卫星正在进行的新的硬x射线银河面调查。这个小组的所有观测（在x射线和无线电波长上的批准和建议）都是非专有的，他们打算遵循FIRST调查模式创建一个公共网站，一旦它们被构建和验证，就可以提供所有简化的图像。因此，这项调查将为任何从事银河系天文学工作的天文学家提供有用的数据库。然而，这些研究人员已经确定了一些他们打算关注的具体问题：银河系超新星遗迹的完整普查，大质量恒星形成的普查，以及吸积动力双星系统完整样本的定义。这些调查将为研究银河系中大质量恒星的形成打开一扇新的窗口。所有由质量大于B0的恒星提供动力的HII区域都将被银河系另一侧的太阳圈清楚地看到，因为射电源与MSX卫星在飞机的中红外地图上探测到的红外发射相一致；此外，许多这样的恒星形成复合体将在xmm -牛顿的地图中被探测到，提供了从x射线吸收柱密度估计的距离。该小组将使用MDM 2.4m望远镜上的新红外摄像机跟踪所有HII候选区域。结果将是迄今为止对银河系中大质量恒星形成的最完整的普查。通过对XMM牛顿图像中选定的x射线点源样本进行广泛的光学和近红外跟踪，得出了几种x射线瞬态和稳定双星的光度函数，其亮度将比现有数据所允许的暗2-3个数量级，为近距离双星演化和吸积模型提供了重要的新约束。随着x射线和射电观测时间的分配，加上一台新的8K光学相机和MDM 2.4m望远镜上的近红外成像仪/光谱仪，以及利克和凯克天文台的使用权，这些研究人员拥有了适当的资源，可以提供一个引人注目的银河系新视图。* * *

AST 020655HelfandThe majority of stellar births and stellar deaths in the Milky Way take place shrouded fromthe view of optical telescopes. Centimeter radio waves and hard X-rays can penetrate the gas anddust which obscure our vision, but the limited angular resolution and sensitivity of all previoussearches has left us peering through the gas darkly in an attempt to construct a census of starformation and demise in the Galaxy. Drs. David Helfand, at Columbia University, and Robert Becker, at the University of California at Davis, will carry out a new survey of the Galactic Plane with the Very Large Array (VLA), as well as extensive optical and near-infrared follow up observations, to complement a new hard X-ray Galactic plane survey now underway using the XMM-Newton satellite. All of this group's observations (approved and proposed, at X-ray and radio wavelengths) are nonproprietary, and they intend to follow the FIRST survey model in creating a public website which will make available all reduced images as soon as they are constructed and verified. Thus, thesurvey will provide databases of use to any astronomer working in Galactic astronomy. However,these researchers have identified a number of specific problems on which they intend to focus: a complete census of Galactic supernova remnants, a census of massive star formation, and the definition of complete samples of accretion-powered binary systems. The surveys will open a new window on massive star formation in the Milky Way. All HII regions powered by stars more massive than B0 will be clearly visible to the solar circle on the opposite side of the Galaxy as radio sources coincident with infrared emission detected in the MSX satellite mid-infrared maps of the plane; in addition, many of these star formation complexes will be detectable in the XMM-Newton maps, providing a distance estimate from the X-ray absorption column density. This group will follow up all HII region candidates with a new infrared camera on the MDM 2.4m telescope. Theresult will be the most complete census yet of massive star formation in the Galaxy. Luminosity functions for several classes of X-ray transients and steady binaries, derived from extensive optical and near-infrared follow up of selected samples of X-ray point sources from the XMM Newtonimages, will extend 2-3 orders of magnitude fainter than existing data allow, providing important new constraints on close-binary evolution and models for accretion. With both X-ray and radio observing time already allocated, with a new 8K optical camera and a near-infrared imager/spectrometer on the MDM 2.4m telescope and access to the Lick and Keck Observatories, these researchers have the resources in place to provide a striking new view of the Milky Way. ***