The C-Band All Sky Survey: Diffuse Galactic Emission and CMB Polarization

C波段全天巡天（C-BASS）是一种以5 GHz的总强度和线性偏振对整个天空进行的无线电巡天。调查的北方部分将于2012年完成，使用欧文斯谷无线电观测站6.1米天线上的低温接收器，对总强度和线性极化进行优化。2012-2013年将在南非使用7.6米天线上的类似接收器进行一次平行的南部调查。该奖项支持北方调查的完成以及结果的出版和解释。C-BASS将是第一次全天空调查弥漫银河系发射的频率足够低，以同步辐射为主，但足够高，不受法拉第旋转效应的影响。它将提供有关星际介质、银河磁场和辐射机制的新信息。还需要C-BASS数据来改善偏振宇宙微波背景辐射（CMB）与前景辐射的分离。微波背景辐射的偏振是由WMAP和普朗克卫星，以及一些目前和未来的地面和气球实验测量的。这些实验的一个主要目标是测量B模式偏振信号，这有望提供有关暴胀时代的信息-特别是暴胀的能量尺度-以及大统一能量下的物理学。这就要求将宇宙微波背景辐射与前景辐射分离开来，其精度要比我们目前对银河系前景的理解所能达到的精度更高。C-BASS数据将显著提高前景减法的准确性。这项调查是与牛津大学和曼彻斯特大学（英国）、罗兹大学和哈特拉奥大学（南非）以及KACST（沙特阿拉伯）的小组合作进行的。北方调查的接收器已经在国家科学基金会、牛津大学和曼彻斯特大学的支持下在OVRO建造和部署。南部接收器的建设得到了牛津、曼彻斯特和KACST的支持。C-BASS天空图将在完成后不久免费提供。学生参与仪器的设计和建造以及观察和数据分析。C-BASS团队的成员参与欧文斯谷无线电天文台广泛外联方案的制定和执行。

The C-Band All Sky Survey (C-BASS) is a radio survey at 5 GHz of the entire sky in total intensity and linear polarization. The northern part of the survey will be completed in 2012 using a cryogenic receiver, optimized for both total intensity and linear polarization, on a 6.1-meter antenna at the Owens Valley Radio Observatory. A parallel southern survey will be conducted in 2012-2013 using a similar receiver on a 7.6-meter antenna in South Africa. This award supports the completion of the northern survey and the publication and interpretation of the results. The C-BASS will be the first all-sky survey of diffuse Galactic emission at a frequency low enough to be dominated by synchrotron radiation but high enough to be uncorrupted by Faraday rotation effects. It will provide new information about the interstellar medium, the Galactic magnetic field, and radiation mechanisms. The C-BASS data are also needed to improve the separation of the polarized cosmic microwave background (CMB) from foreground emission. The CMB polarization is measured by the WMAP and Planck satellites, and by several current and future ground-based and balloon-borne experiments. A major goal for these experiments is to measure the B-mode polarization signal, which is expected to provide information about the epoch of inflation - in particular, the energy scale of inflation - and about physics at grand unification energies. This requires that the CMB is separated from foreground emission with higher accuracy than it is possible with our current understanding of Galactic foregrounds. The C-BASS data will significantly improve the accuracy of foreground subtraction. The survey is conducted in collaboration with groups at the Universities of Oxford and Manchester (UK), Rhodes University and HartRAO (South Africa), and KACST (Saudi Arabia). The receiver for the northern survey has been constructed and deployed at OVRO with support from the NSF and Oxford and Manchester universities. Construction of the southern receiver has been supported by Oxford, Manchester, and KACST. The The C-BASS sky maps will be made freely available soon after completion. Students are involved in the design and construction of the instrumentation as well as the observations and data analysis. Members of the C-BASS team participate in the development and execution of broad outreach programs at The Owens Valley Radio Observatory.