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In-orbit timing calibration of the Insight-Hard X-ray Modulation Telescope

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 نشر من قبل Youli Tuo
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present the timing system and the performances of the three payloads onboard the Insight-Hard X-ray Modulation Telescope (Insight-HXMT). Insight-HXMT carries three main payloads onboard: the High Energy X-ray telescope (HE, 20-250 keV), the Medium Energy X-ray telescope (ME, 5-30 keV) and the low Energy X-ray telescope (LE, 1-10 keV). We have reported the results of time-cumulative pulse profiles and period evolution using long-term monitoring data of the Crab pulsar. To compare the measurement of the time of arrivals (ToAs) on Crab pulsar, we use the quasi-simultaneous Crab observation with the X-ray Timing Instrument (XTI) on-board the Neutron star Interior Composition Explorer (NICER). The systematic errors of the timing system are determined to be 12.1 {mu}s, 8.6 {mu}s, and 15.8 {mu}s for HE, ME and LE respectively. The timing offsets are delayed with respect to NICER about 24.7 {mu}s, 10.1 {mu}s and 864.7 {mu}s for HE, ME and LE respectively.

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