14 Comae Berenices
Star in the constellation Coma Berenices
14 Comae Berenices is a single[3] star in the northern constellation of Coma Berenices , and is the second brightest[8] member of the Coma Star Cluster .[3] It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.95.[2] Parallax measurements place the star at a distance of about 266 light years .[1]
The spectrum of this star is peculiar and it has been assigned a number of different stellar classifications : A5, F0p, F0 III Sr , F0 vp,[3] F1 IV: np Sr shell ,[5] A9 IV np Sr II ,[10] F1 IV,[11] and A9 V + shell .[12] Abt & Morrell (1995) designated this a Lambda Boötis star but this was later refuted.[10] No surface magnetic field has been detected on 14 Comae Bernices.[13]
14 Comae Berenices is a well-known[12] [8] shell star with a high rate of spin, showing a projected rotational velocity of 226 km/s.[7] This is giving the star an oblate shape with an equatorial bulge that is 12% larger than the polar radius.[4] It is radiating 76[5] times the Sun's luminosity from its photosphere at an effective temperature of 7,300 K.[8]
References
^ 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 .
^ a b c Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues . 2237 . Bibcode :2002yCat.2237....0D .
^ a b c d Abou Elazm, M. S. (October 1993), "The composite spectrum of the A type star 14 Comae", Astrophysics and Space Science , 208 (1): 1–4, Bibcode :1993Ap&SS.208....1A , doi :10.1007/BF00658127 , S2CID 123520053
^ a b van Belle, Gerard T. (March 2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review , 20 (1): 51, arXiv :1204.2572 , Bibcode :2012A&ARv..20...51V , doi :10.1007/s00159-012-0051-2 , S2CID 119273474
^ a b c d 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 .
^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters . 32 (11): 759–771. arXiv :1606.08053 . Bibcode :2006AstL...32..759G . doi :10.1134/S1063773706110065 . S2CID 119231169 .
^ a b c d Pizzolato, N.; et al. (2000). "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases". Astronomy and Astrophysics . 361 : 614. Bibcode :2000A&A...361..614P .
^ a b c d e Dominy, J. F.; Smith, M. A. (1977). "A spectroscopic study of 14 Comae and other A-type shell stars". Astrophysical Journal . 217 : 494. Bibcode :1977ApJ...217..494D . doi :10.1086/155598 .
^ "14 Com" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-01-02 .
^ a b Murphy, Simon J.; et al. (October 2015), "An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue", Publications of the Astronomical Society of Australia , 32 : 43, arXiv :1508.03633 , Bibcode :2015PASA...32...36M , doi :10.1017/pasa.2015.34 , S2CID 59405545 , e036
^ Gray, R. O.; et al. (2001). "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars". The Astronomical Journal . 121 (4): 2148. Bibcode :2001AJ....121.2148G . doi :10.1086/319956 .
^ a b Abt, Helmut A.; Willmarth, Daryl W. (August 1999), "Binaries in the Praesepe and Coma Star Clusters and Their Implications for Binary Evolution", The Astrophysical Journal , 521 (2): 682–690, Bibcode :1999ApJ...521..682A , doi :10.1086/307569 , S2CID 119772785
^ Kudryavtsev, D. O.; et al. (November 2006). "New magnetic chemically peculiar stars" . Monthly Notices of the Royal Astronomical Society . 372 (4): 1804–1828. Bibcode :2006MNRAS.372.1804K . doi :10.1111/j.1365-2966.2006.10994.x .