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arXiv · 1908.08186

Discovery of an Outbursting 12.8 Minute Ultracompact X-Ray Binary

P. Pietrukowicz·P. Mroz·A. Udalski·I. Soszynski·J. Skowron
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Abstract

We report the discovery of OGLE-UCXB-01, a 12.8 minute variable object located in the central field of Galactic bulge globular cluster Djorg 2. The presence of frequent, short-duration brightenings at such an ultrashort period in long-term OGLE photometry together with the blue color of the object in Hubble Space Telescope images and the detection of moderately hard X-rays by Chandra observatory point to an ultracompact X-ray binary system. The observed fast period decrease makes the system a particularly interesting target for gravitational-wave detectors such as the planned Laser Interferometer Space Antenna.

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P. Pietrukowicz, P. Mroz, A. Udalski, I. Soszynski, J. Skowron. 2019-08-22. Discovery of an Outbursting 12.8 Minute Ultracompact X-Ray Binary. https://doi.org/10.3847/2041-8213/ab372d

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