论文标题
John A. Galt望远镜的表征，用于无线电的无线电图。
Characterization of the John A. Galt telescope for radio holography with CHIME
论文作者
论文摘要
加拿大氢强度映射实验（Chime）将测量天体中性氢的21 cm发射，以探测红移Z = 0.8-2.5的大规模结构。但是，检测基本上更明亮的前景的21厘米信号仍然是一个关键挑战。由于21厘米和前景发射之间的动态范围很高，因此需要对仪器系统（尤其是望远镜梁）进行精美的校准，以便成功地滤除前景。一种用于实现铃束高忠诚度测量的技术是无线电全息图，其中每个链的类似物输入中的每个信号与共同位置的参考天线的信号相关，即26 m John A. Galt望远镜，作为26 m Galt望远镜的26 m Galt望远镜跟踪了亮点源于chime的光点源。在这项工作中，我们介绍了Galt望远镜的几种特性的分析。我们采用了几种明亮来源的漂移范围测量以及从408 MHz Haslam图得出的背景估计来估计GALT系统温度。为了确定Galt望远镜的光束形状，我们执行和分析了明亮无线电源CassiopeiaA的光栅扫描A。
The Canadian Hydrogen Intensity Mapping Experiment (CHIME) will measure the 21 cm emission of astrophysical neutral hydrogen to probe large scale structure at redshifts z=0.8-2.5. However, detecting the 21 cm signal beneath substantially brighter foregrounds remains a key challenge. Due to the high dynamic range between 21 cm and foreground emission, an exquisite calibration of instrument systematics, notably the telescope beam, is required to successfully filter out the foregrounds. One technique being used to achieve a high fidelity measurement of the CHIME beam is radio holography, wherein signals from each of CHIME's analog inputs are correlated with the signal from a co-located reference antenna, the 26 m John A. Galt telescope, as the 26 m Galt telescope tracks a bright point source transiting over CHIME. In this work we present an analysis of several of the Galt telescope's properties. We employ driftscan measurements of several bright sources, along with background estimates derived from the 408 MHz Haslam map, to estimate the Galt system temperature. To determine the Galt telescope's beam shape, we perform and analyze a raster scan of the bright radio source Cassiopeia A. Finally, we use early holographic measurements to measure the Galt telescope's geometry with respect to CHIME for the holographic analysis of the CHIME and Galt interferometric data set.
