Optical Dust Polarization Measurements in the Galactic Halo: A Tool for Detecting Primordial Gravity Waves, Studying Galactic Magnetic Field and Determining Dust Properties

大卫·斯珀格尔博士(普林斯顿大学)将使用对银晕中2000颗恒星的光学尘埃偏振的档案测量来生成偏振模板图，用于微波背景研究。由于尘埃颗粒的偏振毫米波和亚毫米波辐射是宇宙微波背景(CMB)偏振研究的主要前景，这个模板将对探测原始引力波的努力至关重要。尘埃偏振测量还将用于研究尘埃颗粒的性质，测量银盘中磁场湍流的幅度和频谱，以及确定尘埃消光图的零点。尘埃偏振测量将有助于宇宙学家探测原始引力波。这些引力波是在大爆炸的最初时刻产生的。它们的发现将引起科学家和公众的广泛兴趣。这一研究计划将导致尘埃模板地图的发布，这些地图将被目前正在开发的许多偏振实验广泛使用。改进后的尘埃消光图零点测量将被广泛用于河外研究。该研究项目还将培养本科生和研究生。通过让学生参与实质性研究，该项目将有助于培养下一代美国科学家。

Dr. David Spergel (Princeton University) will use archival measurements of optical dust polarization to 2000 stars in the galactic halo to generate a polarization template map for microwave background studies. Because polarized millimeter and sub-millimeter emission from dust grains is the dominant foreground for cosmic microwave background (CMB) polarization studies, this template will be essential for efforts to detect primordial gravitational waves. The dust polarization measurements will also be used to study the properties of dust grains, to measure the amplitude and spectrum of magnetic field turbulence in the galactic disk and to fix the zero-point of the dust extinction maps.The dust polarization measurements will help cosmologists working to detect primordial gravitational waves. These gravitational waves were produced during the first moments of the big bang. Their detection would be of broad interest to both scientists and the general public. This research program will lead to the release of dust template maps that will be widely used by many polarization experiments now under development. The improved measurements of the zero-point in dust extinction maps would be widely used in extragalactic studies. This research program will also train undergraduate and graduate students. By engaging students in substantive research, the program will help to develop the next generation of U.S. scientists.