BN Camelopardalis

Summary

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]

BN Camelopardalis

A visual band light curve for BN Camelopardalis, adapted from Adelman (1997)[1]
Observation data
Epoch J2000      Equinox J2000
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 mas[2]
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

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 edit

  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. Bibcode:1997PASP..109....9A. doi:10.1086/133853. S2CID 122538111.
  2. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  3. ^ a b c d e f Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  4. ^ a b c d 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, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
  5. ^ a b 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, Bibcode:1995ApJS...99..135A, doi:10.1086/192182.
  6. ^ a b c d 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. arXiv:1703.05218. Bibcode:2017MNRAS.468.2745N. doi:10.1093/mnras/stx674. S2CID 119215348.
  7. ^ a b c d North, P. (June 1998), "Do SI stars undergo any rotational braking?", Astronomy and Astrophysics, 334: 181–187, arXiv:astro-ph/9802286, Bibcode:1998A&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, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763
  9. ^ "BN Cam". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-08-14.
  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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  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, arXiv:0710.1554, Bibcode:2007A&A...475.1053A, doi:10.1051/0004-6361:20078189, S2CID 54850596.
  12. ^ a b 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, Bibcode:2007PASP..119..733A, doi:10.1086/520627.
  13. ^ Renson, P.; Manfroid, J. (May 2009), "Catalogue of Ap, HgMn and Am stars", Astronomy and Astrophysics, 498 (3): 961–966, Bibcode:2009A&A...498..961R, doi:10.1051/0004-6361/200810788
  14. ^ Watson, Christopher (4 January 2010). "BN Camelopardalis". The International Variable Star Index. American Association of Variable Star Observers. Retrieved 26 May 2015.