Astronomy:BN Camelopardalis

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Short description: Star in the constellation Camelopardalis
BN Camelopardalis
BNCamLightCurve.png
A visual band light curve for BN Camelopardalis, adapted from Adelman (1997)[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Camelopardalis
Right ascension  05h 12m 22.43769s[2]
Declination +73° 56′ 48.03820″[2]
Apparent magnitude (V) 5.49[3] (5.34 to 5.58)[4]
Characteristics
Spectral type B9.5VpSi[5]
B−V color index −0.108±0.003[3]
Variable type α2 CVn[4]
Astrometry
Radial velocity (Rv)+9.3±2.8[3] km/s
Proper motion (μ) RA: +6.033[2] mas/yr
Dec.: –27.088[2] mas/yr
Parallax (π)10.5286 ± 0.2275[2] mas
Distance310 ± 7 ly
(95 ± 2 pc)
Absolute magnitude (MV)+0.13[3]
Details
Mass3.05±0.13[6] M
Radius2.9±0.4[7] R
Luminosity110[6] L
Surface gravity (log g)4.15±0.11[7] cgs
Temperature11,561[6] K
Rotation2.73332 days[7]
Rotational velocity (v sin i)23[8] km/s
Other designations
BN Cam, BD+73°274, FK5 2387, HD 32650, HIP 24254, HR 1643, SAO 5455[9]
Database references
SIMBADdata

BN Camelopardalis is a suspected astrometric binary[10] in the northern circumpolar constellation of Camelopardalis. It appears as a variable star that is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude that fluctuates around 5.49.[3] The system is located at a distance of around 310 light years from the Sun based on parallax,[2] and is drifting further away with a radial velocity of +9 km/s.[3]

The visible component is a weakly magnetic[11] chemically peculiar star[12][13] with a stellar classification of B9.5VpSi,[5] matching a B-type main-sequence star with an anomalous abundance of silicon. It is a variable star[14] that ranges in brightness from 5.34 down to 5.58.[4] Samus et al. (2017) have it categorized as an α2 Canum Venaticorum variable with a period of 2.7347 days,[4] while Adelman and Sutton (2007) found a period of 2.73501 days.[12] The star has three times the mass and radius of the Sun and is radiating 110 times the Sun's luminosity from its photosphere at an effective temperature of 11,561 K.[7][6]

References

  1. Adelman, Saul J. (January 1997). "Strömgren uvby Photometry of the Magnetic Chemically Peculiar Stars HR 1643, θ Aur, 49 Cam, and HR 3724". Publications of the Astronomical Society of the Pacific 109: 9–14. doi:10.1086/133853. Bibcode1997PASP..109....9A. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  4. 4.0 4.1 4.2 4.3 Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports 61 (1): 80, doi:10.1134/S1063772917010085, Bibcode2017ARep...61...80S. 
  5. 5.0 5.1 Abt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement Series 99: 135, doi:10.1086/192182, Bibcode1995ApJS...99..135A. 
  6. 6.0 6.1 6.2 6.3 Netopil, Martin; Paunzen, Ernst; Hümmerich, Stefan; Bernhard, Klaus (2017). "An investigation of the rotational properties of magnetic chemically peculiar stars". Monthly Notices of the Royal Astronomical Society 468 (3): 2745–2756. doi:10.1093/mnras/stx674. Bibcode2017MNRAS.468.2745N. 
  7. 7.0 7.1 7.2 7.3 North, P. (June 1998), "Do SI stars undergo any rotational braking?", Astronomy and Astrophysics 334: 181–187, Bibcode1998A&A...334..181N. 
  8. Royer, F. et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics 393 (3): 897–911, doi:10.1051/0004-6361:20020943, Bibcode2002A&A...393..897R 
  9. "BN Cam". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=BN+Cam. 
  10. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  11. Aurière, M. et al. (December 2007), "Weak magnetic fields in Ap/Bp stars. Evidence for a dipole field lower limit and a tentative interpretation of the magnetic dichotomy", Astronomy and Astrophysics 475 (3): 1053–1065, doi:10.1051/0004-6361:20078189, Bibcode2007A&A...475.1053A. 
  12. 12.0 12.1 Adelman, Saul J.; Sutton, Jason M. (July 2007), "FCAPT uvby Photometry of the mCP Stars BN Cam, EP Vir, FF Vir, and HD 184905", The Publications of the Astronomical Society of the Pacific 119 (857): 733–741, doi:10.1086/520627, Bibcode2007PASP..119..733A. 
  13. Renson, P.; Manfroid, J. (May 2009), "Catalogue of Ap, HgMn and Am stars", Astronomy and Astrophysics 498 (3): 961–966, doi:10.1051/0004-6361/200810788, Bibcode2009A&A...498..961R 
  14. Watson, Christopher (4 January 2010). "BN Camelopardalis". The International Variable Star Index. American Association of Variable Star Observers. http://www.aavso.org/vsx/index.php?view=detail.top&oid=4624. Retrieved 26 May 2015.