中文

宇宙学大角尺度巡天仪(CLASS)两年观测:Q 波段大气圆偏振的首次探测

天体物理仪器与方法 2020-02-03 v2

摘要

地球磁场引起大气中分子氧磁偶极跃迁的塞曼分裂,从而在毫米波频段产生偏振辐射。该偏振辐射主要为圆偏振,并作为前景以偶极形天空图样呈现于对偏振敏感的地面宇宙微波背景实验(如能够测量大角尺度圆偏振的宇宙学大角尺度巡天仪(CLASS))。利用大气辐射理论与辐射传输形式,我们对该信号的预期振幅与空间分布进行建模,并针对位于智利北部阿塔卡马沙漠的 CLASS 观测台址评估该模型。随后,利用 CLASS Q 波段望远镜在 32.3 GHz 至 43.7 GHz 的两年观测数据,我们给出了该信号的探测结果,并将观测信号与模型预测进行比较。我们恢复出磁北与真北之间夹角为 (5.5±0.6)(-5.5 \pm 0.6)^\circ,与 CLASS 观测台址预期的 5.9-5.9^\circ 一致。当比较拟合到模拟与数据导出天图的偶极图样时,偶极方向在 1 度内吻合,且测量振幅在 20%{\sim}20\% 内吻合。

关键词

引用

@article{arxiv.1911.01016,
  title  = {Two-year Cosmology Large Angular Scale Surveyor (CLASS) Observations: A First Detection of Atmospheric Circular Polarization at Q Band},
  author = {Matthew A. Petroff and Joseph R. Eimer and Kathleen Harrington and Aamir Ali and John W. Appel and Charles L. Bennett and Michael K. Brewer and Ricardo Bustos and Manwei Chan and David T. Chuss and Joseph Cleary and Jullianna Denes Couto and Sumit Dahal and Rolando Dünner and Thomas Essinger-Hileman and Pedro Fluxá Rojas and Dominik Gothe and Jeffrey Iuliano and Tobias A. Marriage and Nathan J. Miller and Carolina Núñez and Ivan L. Padilla and Lucas Parker and Rodrigo Reeves and Karwan Rostem and Deniz Augusto Nunes Valle and Duncan J. Watts and Janet L. Weiland and Edward J. Wollack and Zhilei Xu},
  journal= {arXiv preprint arXiv:1911.01016},
  year   = {2020}
}

备注

13 pages, 7 figures, published in ApJ