U Coronae Borealis

{{Short description|Algol-type eclipsing binary star in the constellation Corona Borealis}}{{confuse|Upsilon Coronae Borealis}}

{{starbox short

|constell= Corona Borealis

|name= U Coronae Borealis

|type= B6 V + F8 III-IV

|ra= {{RA|15|18|11.35252}}{{cite simbad|title = V* U CrB|access-date = 10 March 2015}}

|dec= {{DEC|+31|38|49.4159}}

| names = {{odlist|HD=136175|HIP=74881|BD=+32° 2569|SAO=64619}}

| Simbad = U+CrB

}}

File:UCrBLightCurve.png light curve for U Coronae Borealis, adapted from et al. (2003)]]

U Coronae Borealis (U CrB) is an Algol-type eclipsing binary star system in the constellation Corona Borealis. Its apparent magnitude varies between 7.66 and 8.79 over a period of 3.45 days.{{cite web|url=http://www.aavso.org/vsx/index.php?view=detail.top&oid=10603 |title=U Coronae Borealis|author=VSX|date=4 January 2010|work=AAVSO Website|publisher=American Association of Variable Star Observers|access-date=10 March 2015}} The component stars are a blue-white main sequence star of spectral type B6V and a cooler yellow-white subgiant star of spectral type F8III-IV.{{cite journal|author1=Ibanoǧlu, C. |author2=DervişoǧLu, A. |author3=Ćakırlı, Ö. |author4=Sipahi, E. |author5=Yüce, K. |date=2012|title=Carbon deficiencies in the primaries of some classical Algols|journal=Monthly Notices of the Royal Astronomical Society|volume=419|issue=2|pages=1472–79|bibcode=2012MNRAS.419.1472I|arxiv = 1109.1939 |doi = 10.1111/j.1365-2966.2011.19812.x |doi-access=free |s2cid=119295168 }}