论文标题
Nustar X射线望远镜的定时校准
Timing Calibration of the NuSTAR X-ray Telescope
论文作者
论文摘要
核光谱望远镜阵列（Nustar）任务是硬X射线（3-79 KEV）频段中的第一个聚焦X射线望远镜。在可以在该能带中研究的现象中，有些需要高时间分辨率和稳定性：旋转驱动和积聚毫秒的脉冲星，黑洞和中子星的快速变化，X射线爆发等等。此外，X射线光子的时间戳与UTC的良好比对是对快速天体物理过程多仪器研究的关键。在本文中，我们描述了Nustar任务的定时校准。特别是，我们提出了一种纠正载体温度补偿晶体振荡器的温度依赖性频率响应的方法。加上在下行链路通过期间获得的航天器时钟偏移的测量，这可以精确地表征振荡器的行为。典型观察结果的校准Nustar事件时间戳显示为〜65 microsec的精度。
The Nuclear Spectroscopic Telescope Array (NuSTAR) mission is the first focusing X-ray telescope in the hard X-ray (3-79 keV) band. Among the phenomena that can be studied in this energy band, some require high time resolution and stability: rotation-powered and accreting millisecond pulsars, fast variability from black holes and neutron stars, X-ray bursts, and more. Moreover, a good alignment of the timestamps of X-ray photons to UTC is key for multi-instrument studies of fast astrophysical processes. In this Paper, we describe the timing calibration of the NuSTAR mission. In particular, we present a method to correct the temperature-dependent frequency response of the on-board temperature-compensated crystal oscillator. Together with measurements of the spacecraft clock offsets obtained during downlinks passes, this allows a precise characterization of the behavior of the oscillator. The calibrated NuSTAR event timestamps for a typical observation are shown to be accurate to a precision of ~65 microsec.
