Psi Virginis

Psi Virginis (ψ Vir, ψ Virginis) is a suspected[4] binary star[3] system in the zodiac constellation of Virgo. It can be seen with the naked eye and has an apparent visual magnitude of +4.80.[2] Based upon the annual parallax shift of 5.99 milliarcseconds, the distance to this star is roughly 540 light years. The angular size of Psi Virginis was measured on December 26, 1975 during an occultation by the Moon, yielding the estimate 6.5±0.3 milliarcsec.[8]

ψ Virginis
Location of ψ Virginis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Virgo
Right ascension  12h 54m 21.16342s[1]
Declination −09° 32′ 20.3783″[1]
Apparent magnitude (V) +4.80[2]
Characteristics
Spectral type M3 IIICa-1[3]
U−B color index +1.57[2]
B−V color index +1.58[2]
Astrometry
Radial velocity (Rv)+12.82[4] km/s
Proper motion (μ) RA: −18.08[1] mas/yr
Dec.: −19.52[1] mas/yr
Parallax (π)5.99 ± 0.23[1] mas
Distance540 ± 20 ly
(167 ± 6 pc)
Absolute magnitude (MV)−1.34[5]
Details
Luminosity1,448[6] L☉
Temperature3,687[6] K
Other designations
ψ Vir, 40 Virginis, BD−08°3449, FK5 1335, HD 112142, HIP 62985, HR 4902, SAO 139033[7]
Database references
SIMBADdata

The primary component is an evolved red giant star with a stellar classification of M3 IIICa-1.[3] It is an irregular variable[9] with seven measured pulsation periods ranging from 22.4 to 162.6 days, and amplitudes ranging up to 0.m022.[10] The star is a bright X-ray source with a luminosity of 21.58×1029 ergs s−1.[11] There is a magnitude 8.3 companion at an angular separation of 0.04 arcseconds.[3]

References
  1. van Leeuwen, F. (November 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.
  2. Mermilliod, J.-C. (1986), Compilation of Eggen's UBV data, transformed to UBV (unpublished), SIMBAD, Bibcode:1986EgUBV........0M
  3. 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.
  4. Famaey, B.; et al. (2009). "Spectroscopic binaries among Hipparcos M giants. I. Data, orbits, and intrinsic variations". Astronomy and Astrophysics. 498 (2): 627–640. arXiv:0901.0934. Bibcode:2009A&A...498..627F. doi:10.1051/0004-6361/200810698.
  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.
  6. McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x.
  7. "psi Vir -- Long-period variable star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-19.
  8. Evans, D. S.; et al. (October 1977), "Angular diameter of psi Vir (SAO 139033) and chi 1Ori (SAO 077705)", Astronomical Journal, 82: 828–831, Bibcode:1977AJ.....82..828E, doi:10.1086/112134.
  9. Mennessier, M. O.; et al. (August 2001), "Long period variable stars: galactic populations and infrared luminosity calibrations", Astronomy and Astrophysics, 374: 968–979, arXiv:astro-ph/0105552, Bibcode:2001A&A...374..968M, doi:10.1051/0004-6361:20010764.
  10. Tabur, V.; Bedding, T. R. (2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–61, arXiv:0908.3228, Bibcode:2009MNRAS.400.1945T, doi:10.1111/j.1365-2966.2009.15588.x.
  11. Makarov, Valeri V. (October 2003), "The 100 Brightest X-Ray Stars within 50 Parsecs of the Sun", The Astronomical Journal, 126 (4): 1996–2008, Bibcode:2003AJ....126.1996M, doi:10.1086/378164.
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