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Title: From Active Stars to Black Holes: A Discovery Tool for Galactic X-Ray Sources
Abstract Galactic X-ray sources are diverse, ranging from active M dwarfs to compact object binaries, and everything in between. The X-ray landscape of today is rich, with point source catalogs such as those from XMM-Newton, Chandra, and Swift, each with ≳105sources and growing. Furthermore, X-ray astronomy is on the verge of being transformed through data releases from the all-sky SRG/eROSITA survey. Many X-ray sources can be associated with an optical counterpart, which in the era of Gaia, can be determined to be Galactic or extragalactic through parallax and proper motion information. Here, I present a simple diagram—the “X-ray Main Sequence,” which distinguishes between compact objects and active stars based on their optical color and X-ray-to-optical flux ratio (FX/Fopt). As a proof of concept, I present optical spectroscopy of six exotic accreting WDs discovered using the X-ray Main Sequence as applied to the XMM-Newton catalog. Looking ahead to surveys of the near future, I additionally present SDSS-V optical spectroscopy of new systems discovered using the X-ray Main Sequence as applied to the SRG/eROSITA eFEDS catalog.  more » « less
Award ID(s):
2034437
PAR ID:
10578331
Author(s) / Creator(s):
Publisher / Repository:
PASP
Date Published:
Journal Name:
Publications of the Astronomical Society of the Pacific
Volume:
136
Issue:
5
ISSN:
0004-6280
Page Range / eLocation ID:
054201
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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