UW Coronae Borealis

UW Coronae Borealis

Observational data
Epoch:	J2000.0 [1]
Constellation:	Corona Borealis [1]
Right ascension:	16^h 05^m 45.873^s [1]
Declination:	+25° 51′ 45.17″ [1]

UW Coronae Borealis, also known as MS1603.6+2600, is a low mass X-ray binary star system located in the constellation Corona Borealis.^[1] Astronomer Simon Morris and colleagues discovered the X-ray source in 1990 and were able to match it up with a faint star with an average visual magnitude of 19.4.^[2] The system is thought to be made up of a neutron star that has an accretion disk that draws material from its companion, a star less massive than the Sun. The disk is asymmetrical. The variability of the system is complex, with several periods identified: the two components orbit each other every 111 minutes, while there is another period of 112.6 minutes. The beat period of these is 5.5 days, which is thought to represent the precession of the asymmetrical accretion disk around the neutron star.^[3]

References

1. "UW Coronae Borealis – Low Mass X-ray Binary". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 17 March 2015.
2. Morris, Simon L.; Liebert, James; Stocke, John T.; Gioia, Isabella M.; Schild, Rudy E.; Wolter, Anna (1990). "MS 1603.6 + 2600, an unusual X-ray selected binary system at high Galactic latitude". Astrophysical Journal 365 (20): 686–95. Bibcode:1990ApJ...365..686M. doi:10.1086/169523.
3. Mason, Paul A.; Robinson, Edward L.; Bayless, Amanda J.; Hakala, Pasi J. (2012). "Long-term Optical Observations of Two LMXBS: UW CrB (=MS 1603+260) and V1408 Aql (=4U 1957+115)". The Astronomical Journal 144 (4). Bibcode:2012AJ....144..108M. doi:10.1088/0004-6256/144/4/108.