The spectroscopic performance of x-ray instruments can be affected at high count rates. The effects and mitigation in the optical chain, such as x-ray attenuation filters or de-focusing mirrors, are widely discussed, but those in the signal chain are not. Using the Resolve x-ray microcalorimeter onboard the XRISM satellite, we discuss the effects observed during high count rate measurements and how these can be modeled. We focus on three instrumental effects that impact performance at high count rate: CPU limit, pile up, and electrical cross talk. High count rate data were obtained during ground testing using the flight model instrument and a calibration x-ray source. A simulated observation of GX 13+1 is presented to illustrate how to estimate these effects based on these models for observation planning. The impact of these effects on high count rate observations is discussed.
Cite
@article{arxiv.2312.15588,
title = {High count rate effects in event processing for XRISM/Resolve x-ray microcalorimeter},
author = {Misaki Mizumoto and Masahiro Tsujimoto and Renata S. Cumbee and Megan E. Eckart and Yoshitaka Ishisaki and Caroline A. Kilbourne and Edmund Hodges-Kluck and Maurice A. Leutenegger and Frederick S. Porter and Makoto Sawada and Yoh Takei and Yuusuke Uchida and Shin'ya Yamada and the XRISM Resolve team},
journal= {arXiv preprint arXiv:2312.15588},
year = {2025}
}
Comments
A refereed paper (JATIS) based on this proceeding has been uploaded in arXiv (arXiv:2501.03283). To avoid duplication we have withdrawn this version