Using the Sun to Measure the Primary Beam Response of the Canadian Hydrogen Intensity Mapping Experiment

Abstract We present a beam pattern measurement of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) made using Sun as calibration source. As CHIME is pure drift-scan instrument, we rely on seasonal north–south motion to probe at different elevations. This semiannual range in elevation, combined with radio brightness Sun, enables that spans ∼7200 square degrees sky without need move telescope. take advantage observations near solar minimum minimize impact variability, which observed be <10% intensity over observation period. The resulting data set highly complementary other measurements—both terms angular coverage and systematics—and plays an important role ongoing program characterize primary beam.