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arXiv · 2609.38321

An X-ray Extremely wide-field Spectroscopic Surveyor (XESS, or "chess")

W. P. Maksym·M. Ulmer·S. Friedrich·F. Tombesi·R. Arcodia·S. P. Singam·S. Bongiorno·N. Thomas·M. Elvis·Ming Sun·John ZuHone·M. Lynne Saade·Philip Kaaret·Doug Swartz·Erin Hicks·Ming-Yi Lin·Pallavi Patil·Jimmy Irwin·Shrabani Kumar·Kirtan Dixit·Sudip Chakraborty·Andrea Gnarini·Steven Ehlert
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Abstract

We propose an X-ray observatory, the X-ray Extremely wide-field Spectroscopic Surveyor (XESS, pronounced "Chess") to bring high energy resolution X-ray spectroscopy into the era of synoptic surveys and of time domain and multi-messenger astrophysics (TDAMM). Such an observatory is optimally suited to addressing key elements of the 2020 Decadal Survey on Astronomy and Astrophysics.

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W. P. Maksym, M. Ulmer, S. Friedrich, F. Tombesi, R. Arcodia, S. P. Singam, S. Bongiorno, N. Thomas, M. Elvis, Ming Sun, John ZuHone, M. Lynne Saade, Philip Kaaret, Doug Swartz, Erin Hicks, Ming-Yi Lin, Pallavi Patil, Jimmy Irwin, Shrabani Kumar, Kirtan Dixit, Sudip Chakraborty, Andrea Gnarini, Steven Ehlert. 2026-09-29. An X-ray Extremely wide-field Spectroscopic Surveyor (XESS, or "chess"). https://arxiv.org/abs/2609.38321

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