UW Coronae Borealis

UW Coronae Borealis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Corona Borealis
Right ascension 16h 05m 45.873s[1]
Declination +36° 48′ 35.2″[1]
Apparent magnitude (V) 19.7[2]
Other designations
1E 1603.6+2600, 2E 1603.6+2600, 1RXS J160545.3+255131, SDSS J160545.87+255145.1
Database references
SIMBADdata
Six representative white-light light curves for UW Coronae Borealis, adapted from Hakala et al. (2009)[3]

UW Coronae Borealis, also known as MS 1603.6+2600, is a low-mass X-ray binary star system 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.[4] 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.[5]

  1. ^ a b c "UW CrB". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 7 December 2016.
  2. ^ Liu, Q. Z. (2007). "A catalogue of low-mass X-ray binaries in the Galaxy, LMC, and SMC (Fourth edition)". Astronomy and Astrophysics. 469 (2): 807–810. arXiv:0707.0544. Bibcode:2007A&A...469..807L. doi:10.1051/0004-6361:20077303. S2CID 14673570. Retrieved 7 December 2016.
  3. ^ Cite error: The named reference Hakala was invoked but never defined (see the help page).
  4. ^ 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.
  5. ^ 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): 108. Bibcode:2012AJ....144..108M. doi:10.1088/0004-6256/144/4/108. hdl:2152/34339. S2CID 122184568.