Variable star in the constellation Circinus
Gamma Circini , Latinized from γ Circini, is a star system in the constellation Circinus . It was noted as a double star by Herschel in 1835, who estimated the separation as 1 arc second .[11] It is visible to the naked eye with an apparent visual magnitude of 4.51.[2] Based upon an annual parallax shift of 7.27 mas ,[1] it is about 450 light-years away.
A light curve for Gamma Circini, plotted from TESS data[12] This is a wide binary star system and may even be a triple star .[9] The two visible components orbit each other with a preliminary estimated period of 258 years and a large eccentricity of 0.931.[4] As of 2014, the visible components have an angular separation of 0.80 arc seconds on a position angle of 359°.[3]
The primary star, component A, is a B-type subgiant star with a stellar classification of B5 IV.[4] Based upon isochrone curve fitting it is hypothesized to be a pair of matching B5 stars,[9] and is a Be variable with an uncertain maximum.[5] It has an effective temperature of 15,135[9] K and an estimated mass six[8] times that of the Sun. The companion, component B, is an F-type main-sequence star with a stellar classification of F8 V.[2] It has an effective temperature of 4,786[9] K.
^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics , 474 (2): 653–664, arXiv :0708.1752 , Bibcode :2007A&A...474..653V , doi :10.1051/0004-6361:20078357 , S2CID 18759600 .
^ a b c d Buscombe, W.; Barkstrom, B. (1971), "The composite spectrum of gamma Circini", Monthly Notices of the Royal Astronomical Society , 152 : 37–45, Bibcode :1971MNRAS.152...37B , doi :10.1093/mnras/152.1.37 .
^ a b Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog" , The Astronomical Journal , 122 (6): 3466–3471, Bibcode :2001AJ....122.3466M , doi :10.1086/323920 , retrieved 2015-07-22
^ a b c d Malkov, O. Yu.; et al. (2012), "Dynamical masses of a selected sample of orbital binaries", Astronomy & Astrophysics , 546 : A69, Bibcode :2012A&A...546A..69M , doi :10.1051/0004-6361/201219774 .
^ a b Kazarovets, E. V.; et al. (1999). "The 74th Special Name-list of Variable Stars". Information Bulletin on Variable Stars . 4659 : 1. Bibcode :1999IBVS.4659....1K .
^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics , 546 : 14, arXiv :1208.3048 , Bibcode :2012A&A...546A..61D , doi :10.1051/0004-6361/201219219 , S2CID 59451347 , A61.
^ 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 .
^ a b c Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society , 410 (1): 190–200, arXiv :1007.4883 , Bibcode :2011MNRAS.410..190T , doi :10.1111/j.1365-2966.2010.17434.x , S2CID 118629873 .
^ a b c d e f Parsons, Sidney B. (May 2004), "New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions", The Astronomical Journal , 127 (5): 2915–2930, Bibcode :2004AJ....127.2915P , doi :10.1086/383546 .
^ "* gam Cir" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2017-01-13 .((cite web ))
: CS1 maint: postscript (link )
^ Carette, E.; et al. (April 1995), "γ Circinus: a young visual binary with pre-main-sequence component(s)?", Astronomy and Astrophysics , 296 : 139, Bibcode :1995A&A...296..139C .
^ "MAST: Barbara A. Mikulski Archive for Space Telescopes" . Space Telescope Science Institute. Retrieved 29 December 2022 .