Binary star system in the constellation Cetus
HD 11964 is abinary star system located 110[ 1] light-years away from theSun in theequatorial constellation ofCetus . It is visible in binoculars or a telescope but is too faint to be seen with the naked eye, having anapparent visual magnitude of 7.51.[ 2] radial velocity of −9 km/s.[ 5] extrasolar planets have been confirmed to orbit the primary.
The primary, component A, is aG-type main-sequence star with astellar classification of G9VCN+1.[ 3] cyano radical in thespectrum . Houk and Swift (1999) found a class of G8IV, suggesting it is instead a moreevolved subgiant star .[ 10] [ 6] projected rotational velocity of 1.5 km/s.[ 5] [ 6] mass of the Sun and 2.2[ 7] Sun's radius . It is radiating 2.9[ 6] luminosity of the Sun from itsphotosphere at aneffective temperature of 5,321 K.[ 5]
A widebinary companion star was discovered in 2000.[ 11] angular separation of″ position angle of 134°, as of 2015.[ 12] red dwarf with a class of M0V,[ 4] [ 1]
In August 2005, two planets were discovered orbiting the star, the innermost like Neptune and another like Jupiter orbiting at 3.34 AU. However, the second planet (HD 11964 b ) was not confirmed until May 2007. In September 2007,P.C. Gregory claimed that there was a third planet in the system on the basis ofBayesian analysis of the radial velocity data. The planet was claimed to have a mass similar to that ofSaturn and located in a 360-day orbit. Gregory cautioned that the close match between the period of this planet to being exactly a year meant that the radial velocity variations may have been caused by insufficient correction for the motion of theEarth in orbit around the Sun.[ 13] Astrophysical Journal in 2009.[ 14]
^a b c d e f g h i j 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 ^a b c d e f g h i j 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 Gray, R. O.; et al. (July 2006). "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample".The Astronomical Journal 132 (1):161– 170.arXiv :astro-ph/0603770 Bibcode :2006AJ....132..161G .doi :10.1086/504637 .S2CID 119476992 . ^a b Alonso-Floriano, F. J.; Morales, J. C.; Caballero, J. A.; Montes, D.; Klutsch, A.; Mundt, R.; Cortés-Contreras, M.; Ribas, I.; Reiners, Ansgar; Amado, P. J.; Quirrenbach, A.; Jeffers, S. V. (2015)."CARMENES input catalogue of M dwarfs" (PDF) .Astronomy & Astrophysics .577 : A128.arXiv :1502.07580 Bibcode :2015A&A...577A.128A .doi :10.1051/0004-6361/201525803 .S2CID 53135130 . [permanent dead link ] ^a b c d e f g h Jofré, E.; et al. (2015). "Stellar parameters and chemical abundances of 223 evolved stars with and without planets".Astronomy & Astrophysics .574 : A50.arXiv :1410.6422 Bibcode :2015A&A...574A..50J .doi :10.1051/0004-6361/201424474 .S2CID 53666931 . ^a b c d e f Ghezzi, L.; et al. (December 2010), "Metallicities of Planet-hosting Stars: A Sample of Giants and Subgiants",The Astrophysical Journal ,725 (1):721– 733,arXiv :1008.3539 Bibcode :2010ApJ...725..721G ,doi :10.1088/0004-637X/725/1/721 ,S2CID 119206634 ^a b van Belle, Gerard T.; von Braun, Kaspar (2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars".The Astrophysical Journal .694 (2):1085– 1098.arXiv :0901.1206 Bibcode :2009ApJ...694.1085V .doi :10.1088/0004-637X/694/2/1085 .S2CID 18370219 . ^ Mann, Andrew W.; et al. (February 2013). "Prospecting in Late-type Dwarfs: A Calibration of Infrared and Visible Spectroscopic Metallicities of Late K and M Dwarfs Spanning 1.5 dex".The Astronomical Journal .145 (2): 15.arXiv :1211.4630 Bibcode :2013AJ....145...52M .doi :10.1088/0004-6256/145/2/52 .S2CID 118481247 . 52. ^ "HD 11964" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2019-11-12 .^ Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars".Michigan Spectral Survey .5 .Bibcode :1999MSS...C05....0H . ^ Allen, C. ; et al. (2000)."Wide binaries among high-velocity and metal-poor stars" .Astronomy and Astrophysics 356 (2):529– 540.Bibcode :2000A&A...356..529A . Archived fromthe original on 2011-07-25. Retrieved2008-10-07 .^ Mason, B. D.; et al. (2014)."The Washington Visual Double Star Catalog" .The Astronomical Journal .122 (6): 3466.Bibcode :2001AJ....122.3466M .doi :10.1086/323920 . Retrieved2015-07-22 . ^ Gregory, P. C. (2007)."A Bayesian periodogram finds evidence for three planets in HD 11964" .Monthly Notices of the Royal Astronomical Society 381 (4):1607– 1616.arXiv :0709.0970 Bibcode :2007MNRAS.381.1607G .doi :10.1111/j.1365-2966.2007.12361.x S2CID 16796923 . ^a b Wright, J. T.; et al. (2009). "Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems".The Astrophysical Journal .693 (2):1084– 1099.arXiv :0812.1582 Bibcode :2009ApJ...693.1084W .doi :10.1088/0004-637X/693/2/1084 .S2CID 18169921 .
HD 11964 System
Star Planets
