Current status of the x-ray mirror for the XL-Calibur experiment
Current status of the x-ray mirror for the XL-Calibur experiment
复制标题
XL-Calibur 实验 X 射线镜的现状
DOI：
10.1117/12.2560928
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Abarr Quincy et al.
中科院分区：
文献类型：
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作者：
Hattori Kengo;Matsumoto Hironori;Abarr Quincy et al.
XL-Calibur是一项气球载硬x射线偏振测量任务，目前预计将于2021年首次飞行。XL-Calibur携带的x射线望远镜由213个Wolter I掠射镜组成，这些镜嵌套在同轴和共焦结构中。光学设计几乎与ASTRO-H卫星上的硬x射线望远镜（HXT）相同。该望远镜最初是为编队飞行天文观测望远镜（FFAST）项目制造的。然而，该望远镜可以用于XL-Calibur，因为FFAST项目在完成之前就终止了。镜面表面涂有Pt/C深度梯度多层膜，通过布拉格反射反射10 keV以上的硬x射线。在30kev下，望远镜的有效面积大于300cm ^2。镜子由壳体中的对准杆支撑，并且每个对准杆具有一系列213条凹槽以容纳镜子。为了获得最佳的光学聚焦，必须通过调整对准杆的位置来调整反射镜的位置。镜面位置的调整是在同步加速器设施SPring-8 BL20B2上使用x射线光束进行的，这个过程被称为光学调谐。首先对第二反射器的位置进行调谐，然后对第一反射器的位置进行调谐。我们在2020年1月进行了第一次光学调谐。第二次调整计划在2020年4月至7月之间进行。本文报道了xl口径硬x射线望远镜的现状。
XL-Calibur is a balloon-borne hard X-ray polarimetry mission, the first flight of which is currently foreseen for 2021. XL-Calibur carries an X-ray telescope consists of consists of 213 Wolter I grazing-incidence mirrors which are nested in a coaxial and cofocal configuration. The optics design is nearly identical to the Hard X-ray Telescope (HXT) on board the ASTRO-H satellite. The telescope was originally fabricated for the Formation Flying Astronomical Survey Telescope (FFAST) project. However, the telescope can be used for XL-Calibur, since the FFAST project was terminated before completion. The mirror surfaces are coated with Pt/C depth-graded multilayers to reflect hard X-rays above 10 keV by Bragg reflection. The effective area of the telescope is larger than 300 cm^2 at 30 keV. The mirrors are supported by alignment bars in the housing, and each of the bars has a series of 213 grooves to hold the mirrors. To obtain the best focus of the optics, the positions of the mirrors have to be adjusted by tuning the positions of the alignment bars. The tuning of the mirror positions is conducted using the X-ray beam at the synchrotron facility SPring-8 BL20B2, and this process is called optical tuning. First the positions of the second reflectors are tuned, and then those of the first reflectors are tuned. We did the first optical tuning in Jan 2020. The second tuning will be planned between April to July, 2020. This paper reports the current status of the hard X-ray telescope for XL-Calibur.