Xi Columbae is a binary star[1] system in the southern constellation of Columba. With an apparent visual magnitude of 4.97,[2] it is faintly visible to the naked eye. Based upon an annual parallax shift of 10.1 mas,[3] it is located around 323 light years from the Sun. The system is a member of the HR 1614 supergroup,[4] and is drifting further away with a radial velocity of +59.5 km/s,[5]

This is an astrometric binary[6] with an orbital period of 1,420.6 days and an eccentricity of 0.39.[1] The primary is an evolved K-type giant star with a stellar classification of K1 III CNII,[7] showing an overabundance of CN in its spectrum. The star has expanded to 16 times the radius of the Sun and is radiating 120 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,743 K.[3] The companion has a mass of at least 59% that of the Sun.[1]

References

  1. ^ Setiawan, J. et al. (July 2004), "Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch", Astronomy and Astrophysics. 421: 241–254, Bibcode:2004A&A...421..241S. doi:10.1051/0004-6361:20041042-1
  2. ^ Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal. 150 (3): 23, arXiv:1507.01466. Bibcode:2015AJ....150...88L. doi:10.1088/0004-6256/150/3/88. S2CID 118505114. 88
  3. ^
  4. ^ Eggen, Olin J. (August 1997), "The Abundance of CN, Calcium and Heavy Elements in High Velocity Stars.", The Astronomical Journal. 114: 825–836, Bibcode:1997AJ....114..825E. doi:10.1086/118516
  5. ^ Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W
  6. ^ 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
  7. ^ Houk, Nancy (1979), "Michigan catalogue of two-dimensional spectral types for the HD stars", Vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H