We have performed tests of the SRG project’s ART-XC telescope’s flight spare units of the mirror system (MS) and the URD focal plane X-ray detector. During the tests, the MS was illuminated by a quasi-parallel X-ray beam from a microfocus tube. By changing the angle between the MS optical axis and the incoming beam we obtained data on vignetting of the effective area of the MS–URD pair at the energies of Cu K-lines. The measurements are in good agreement with our model. Using the model vignetting of the effective area, we determined the ART-XC grasp as a function of energy for singly and doubly reflected events. The grasp reaches ∼31 cm²deg² for singly reflected events at 7.2 keV, ∼44 cm²deg² for doubly reflected events at 8.6 keV and ∼74 cm²deg² for the sum of singly and doubly reflected events at 7.6 keV. The grasp values at 8.1 keV are ∼29.9 cm²deg² for singly reflected events, ∼43.8 cm²deg² for doubly reflected events and ∼73.7 cm²deg² for all events. The ART-XC field of view is ∼2 deg². In its central ∼0.3 deg², sources are imaged and the instrument works in a “telescope” mode. The outer ∼1.7 deg² do not have an imaging capability and the instrument works as a “concentrator” there. We also discuss the possibility of using ART-XC for monitoring bright transient X-ray sources when the observatory will be operating in the survey mode.

中文翻译：

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在IKI对ART-XC / SRG反射镜系统和检测器单元进行地面校准。第三部分

我们已经对SRG项目的ART-XC望远镜的镜面系统（MS）和URD焦平面X射线探测器的飞行备用单元进行了测试。在测试过程中，MS被来自微聚焦管的准平行X射线束照亮。通过改变MS光轴和入射光束之间的角度，我们获得了在Cu K线能量下对MS–URD对有效面积进行渐晕的数据。测量结果与我们的模型非常吻合。使用有效区域的模型渐晕线，我们确定了ART-XC抓地力是单个和双重反射事件的能量函数。对于在7.2 keV，约44 cm ² deg ²的单次反射事件，抓握达到〜31 cm ² deg ²对于8.6 keV和约74 cm ² deg ²的双反射事件，对于7.6 keV的单反射和双反射事件的总和。在8.1千电子伏的把握值~29.9厘米² ℃下²为单独的反射事件，~43.8厘米² ℃下²为两次反射活动和~73.7厘米²度²的所有事件。ART-XC视场约为2 deg ²。在其中心〜0.3度^2处，对源进行成像，并且仪器以“望远镜”模式工作。外部〜1.7度²没有成像功能，该仪器在那里充当“集中器”。当天文台将以勘测模式运行时，我们还将讨论使用ART-XC监视明亮的瞬态X射线源的可能性。