BP Circini

BP Circini

A light curve for BP Circini, plotted from Hipparcos data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Circinus
Right ascension 14h 46m 41.98011s[2]
Declination −61° 27′ 42.9903″[2]
Apparent magnitude (V) 7.37 - 7.71[3]
Characteristics
Spectral type F2/3II + B6V[4]
B−V color index 0.649±0.020[5]
Astrometry
Proper motion (μ) RA: −5.355[2] mas/yr
Dec.: −3.920[2] mas/yr
Parallax (π)0.9952 ± 0.0402 mas[2]
Distance3,300 ± 100 ly
(1,000 ± 40 pc)
Absolute magnitude (MV)−2.91[6]
Orbit[6]
Period (P)20 yr
Semi-major axis (a)15.8 AU
Details
A
Mass5[7] M☉
Radius30.38+6.93
−6.50[2] R☉
Luminosity917±54[2] L☉
Surface gravity (log g)2.75[8] cgs
Temperature6356±23[8] K
B
Mass4.7[6] M☉
Surface gravity (log g)4.0±0.5[7] cgs
Temperature16,000±1,000[7] K
Other designations
BP Cir, CD−60°5320, HD 129708, HIP 72264, SAO 252879, WDS J14467-6128A[9]
Database references
SIMBADdata

BP Circini is a binary star system in the southern constellation of Circinus. It is located at a distance of approximately 3,300 light years from the Sun based on parallax.[2]

The variability of this star was discovered by D. W. Kurtz in 1979.[7] A small-amplitude Cepheid variable,[8] its apparent magnitude ranges from 7.37 to 7.71 over 2.39810 days.[3] A spectroscopic binary, the primary is a yellow-white bright giant of spectral type F2 or F3II.[4] The spectrum shows peculiarities in the metallic lines.[10] The secondary is a 4.7 solar mass (M☉) blue-white main sequence star of spectral type B6.[6]

References

  1. ^ "Hipparcos Tools Interactive Data Access". Hipparcos. ESA. Retrieved 8 December 2021.
  2. ^ a b c d e f g h 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 BSJ (30 November 2013). "BP Circini". AAVSO Website. American Association of Variable Star Observers. Retrieved 24 January 2014.
  4. ^ a b Skiff, B. A. (October 2014), "General Catalogue of Stellar Spectral Classifications", VizieR Online Data Catalog, Bibcode:2014yCat....1.2023S
  5. ^ 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.
  6. ^ a b c d Evans, Nancy Remage; et al. (2013). "Binary Cepheids: Separations and Mass Ratios in 5M ⊙ Binaries". Astronomical Journal. 146 (4): 93, 10 pp. arXiv:1307.7123. Bibcode:2013AJ....146...93E. doi:10.1088/0004-6256/146/4/93. S2CID 34133110.
  7. ^ a b c d Petterson, O. K. L.; et al. (May 2004). "The orbits of southern binary Cepheids". Monthly Notices of the Royal Astronomical Society. 350 (1): 95–112. Bibcode:2004MNRAS.350...95P. doi:10.1111/j.1365-2966.2004.07555.x.
  8. ^ a b c Usenko, I. A.; et al. (December 2014). "Spectroscopic studies of Cepheids in Circinus (AV Cir, BP Cir) and Triangulum Australe (R TrA, S TrA, U TrA, LR TrA)". Astronomy Letters. 40 (12): 800–820. Bibcode:2014AstL...40..800U. doi:10.1134/S1063773714110061. S2CID 122745580.
  9. ^ "V* BP Cir". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 24 January 2014.
  10. ^ Kurtz, D. W. (1979). "HD 129708: A New, Bright, Short-Period Cepheid with an Unusual Spectrum". Monthly Notes of the Astronomical Society of Southern Africa. 38: 36. Bibcode:1979MNSSA..38...36K.