Characterization of a pnCCD-based Camera for Applications at the 100 m X-Ray Test Facility*

Abstract

The 100 m long X-ray test facility (100XF for clarity) in Institute of High Energy Physics of CAS has been playing an increasingly important role in the X-ray astronomy field in China. 100XF has been contributing to the missions under development, such as the Einstein Probe mission. The facility has also been providing support to R&D of focusing X-ray optics in China that will enable future X-ray telescopes to be realized, such as the enhanced X-ray Timing and Polarization (eXTP) mission. A pnCCD-based camera has been employed at 100XF to rapidly measure the performance of the X-ray optics. In this work, we study the performance of the camera and its spectral and imaging applications at 100XF. The camera system can provide a high frame readout rate, with a low readout noise <3 e−. It is sensitive to X-ray photons in the 3–10 keV energy band with a high quantum efficiency exceeding 90%. Actually, the low threshold of detection energy range can reach down to 0.2 keV. The energy resolution can reach 145.2 eV for single events and 154.8 eV for all valid events (including single events and split events) at 6.4 keV. The camera also exhibits excellent imaging capability in both the full frame mode and the windowing mode, with a readout rate of up to 1000 Hz. Finally, a prototype of a focusing X-ray mirror shell of eXTP was smoothly measured with this camera. The obtained on-axis point-spread function and half-power diameter are consistent with expectations. It is proven that the camera can improve the capability of 100XF in characterizing the X-ray optics. This camera will be very useful for performing on-ground calibrations for future X-ray telescope missions.

Characterization of the eXTP-LAD collimators

“…As the MCP rotates, the angle between the incident photons and the MCP normal increases, thus simulating photons entering the MCP with different angles. Two detectors are used to record the MCP response: a singlepixel Silicon Drift Detector (SDD) by Amptek with an effective area of 25 mm 2 , and the Color X-ray Camera (CXC) pn-CCD [9]. The detectors are positioned at different distances from the MCP during the various phases of the measurement campaign.…”

“…Figure 5(a) shows the configuration for the tests with the CXC, a pn-CCD featuring 264×264 pixels with a size of 48 µm×48 µm [9]. The MCP, which has been etched for the standard etching time (section 3.4), it can be rotated about different axes with a precision better than 10 ′′ , as well as moved completely out of the beam in order to measure the flat field photon rate on the CXC.…”

A Thermo-Optical Test Device Utilizing the 100-m X-ray Test Facility

“…The 100-m X-ray Test Facility (100XF) is built at the Institute of High Energy Physics (IHEP) in Beijing, serving as a calibration facility for astronomical science [1]. This facility has successfully conducted X-ray calibrations for the Hard X-ray Modulation Telescope (Insight-HXMT) [2], the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) [3] and the Einstein Probe (EP) [4,5], yielding satisfactory test results. In the development process of most scientific satellites, especially those with X-ray detection scientific payloads, testing the X-ray performance of optical components is common and important.…”