The sensitivity of astronomical X-ray detectors is limited by the instrumental background. The background is especially important when observing low surface brightness sources that are critical for many of the science cases targeted by future X-ray observatories, including Athena and future US-led flagship or probe-class X-ray missions. Above 2keV, the background is dominated by signals induced by cosmic rays interacting with the spacecraft and detector. We develop novel machine learning algorithms to identify events in next-generation X-ray imaging detectors and to predict the probability that an event is induced by a cosmic ray vs. an astrophysical X-ray photon, enabling enhanced filtering of the cosmic ray-induced background. We find that by learning the typical correlations between the secondary events that arise from a single primary, machine learning algorithms are able to successfully identify cosmic ray-induced background events that are missed by traditional filtering methods employed on current-generation X-ray missions, reducing the unrejected background by as much as 30 per cent.
@article{arxiv.2208.07906,
title = {Reducing the background in X-ray imaging detectors via machine learning},
author = {D. R. Wilkins and S. W. Allen and E. D. Miller and M. Bautz and T. Chattopadhyay and R. Foster and C. E. Grant and S. Hermann and R. Kraft and R. G. Morris and P. Nulsen and G. Schellenberger},
journal= {arXiv preprint arXiv:2208.07906},
year = {2022}
}
Comments
Proceedings of the SPIE, Astronomical Telescopes and Instrumentation, Space Telescopes and Instrumentation 2022: Ultraviolet to Gamma Ray