Pi Pavonis

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Pi Pavonis
Pavo constellation map.svg
Red circle.svg
Location of π Pavonis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Pavo
Right ascension  18h 08m 34.81459s[1]
Declination −63° 40′ 06.7906″[1]
Apparent magnitude (V) 4.33[2]
Characteristics
Spectral type kA4hF0mF2 III[3]
U−B color index +0.17[4]
B−V color index +0.23[4]
Astrometry
Radial velocity (Rv)−15.60[5] km/s
Proper motion (μ) RA: +18.02[1] mas/yr
Dec.: -207.57[1] mas/yr
Parallax (π)25.09 ± 0.17[1] mas
Distance130.0 ± 0.9 ly
(39.9 ± 0.3 pc)
Absolute magnitude (MV)1.33[2]
Details
Mass2.15[6] M
Radius2.84+0.42
−0.03
[7] R
Luminosity24.69±0.36[7] L
Surface gravity (log g)3.81[8] cgs
Temperature7,632+50
−510
[7] K
Metallicity [Fe/H]0.27[8] dex
Rotational velocity (v sin i)30.0[9] km/s
Age630[6] Myr
Other designations
π Pav, CPD−63°4292, FK5 3437, GC 24665, HD 165040, HIP 88866, HR 6745, SAO 254147[10]
Database references
SIMBADdata

π Pavonis, Latinized as Pi Pavonis, is a candidate astrometric binary[11] star system in the constellation Pavo. It is a white-hued star that is visible to the naked eye as a faint point of light with an apparent visual magnitude of 4.33.[2] The distance to this object is 130 light years based on parallax,[1] but it is drifting closer to the Sun with a radial velocity of −15.6 km/s.[5]

The visible component is an chemically peculiar star that displays an abundance anomaly of strontium.[12][13] Grey et al. (1989) classify it as kA4hF0mF2 III,[3] matching a giant Am star with the calcium K line of an A4 star, the hydrogen lines of a cooler F0 star, and the metal lines of a F2 star. However, Loden and Sundman (1989) don't consider it to be a giant and list it as an Ap star.[12] It is 630[6] million years old with 2.15[6] times the mass of the Sun and 2.8[7] times the Sun's radius. The star is radiating 24.7[7] times the Sun's luminosity from its photosphere at an effective temperature of 7,632 K.[7]

References[edit]

  1. ^ a b c d e f Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
  2. ^ a b c 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. Vizier catalog entry
  3. ^ a b Gray, R. O.; Garrison, R. F. (1989). "The early F-type stars - Refined classification, confrontation with Stromgren photometry, and the effects of rotation". Astrophysical Journal Supplement Series. 69: 301. Bibcode:1989ApJS...69..301G. doi:10.1086/191315.
  4. ^ a b Mermilliod, J. C. (2006). "VizieR Online Data Catalog: Homogeneous Means in the UBV System (Mermilliod 1991)". VizieR On-line Data Catalog: II/168. Originally Published in: Institut d'Astronomie. 2168. Bibcode:2006yCat.2168....0M.Vizier catalog entry
  5. ^ a b Wilson, R. E. (1953). General Catalogue of Stellar Radial Velocities. Carnegie Institution of Washington. Bibcode:1953GCRV..C......0W. LCCN 54001336.
  6. ^ a b c d De Rosa, R. J.; Patience, J.; Wilson, P. A.; Schneider, A.; Wiktorowicz, S. J.; Vigan, A.; Marois, C.; Song, I.; MacIntosh, B.; Graham, J. R.; Doyon, R.; Bessell, M. S.; Thomas, S.; Lai, O. (2013). "The VAST Survey - III. The multiplicity of A-type stars within 75 pc". Monthly Notices of the Royal Astronomical Society. 437 (2): 1216. arXiv:1311.7141. Bibcode:2014MNRAS.437.1216D. doi:10.1093/mnras/stt1932.
  7. ^ a b c d e f 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.
  8. ^ a b Erspamer, D.; North, P. (February 2003). "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs. II. Abundances of 140 A-F stars from ELODIE". Astronomy and Astrophysics. 398: 1121–1135. arXiv:astro-ph/0210065. Bibcode:2003A&A...398.1121E. doi:10.1051/0004-6361:20021711.
  9. ^ Glebocki, R.; Gnacinski, P. (2005). "VizieR Online Data Catalog: Catalog of Stellar Rotational Velocities (Glebocki+ 2005)". VizieR On-line Data Catalog: III/244. Originally Published in: 2005csss...13..571G; 2005yCat.3244....0G. 3244. Bibcode:2005yCat.3244....0G. Vizier catalog entry
  10. ^ "pi Pav". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-12.
  11. ^ 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.
  12. ^ a b Loden, L. O.; Sundman, A. (June 1989). "Giant CP stars?". Journal of Astrophysics and Astronomy. 10: 183–196. Bibcode:1989JApA...10..183L. doi:10.1007/BF02719315.
  13. ^ Renson, P.; Manfroid, J. (2009). "Catalogue of Ap, Hg Mn and Am stars" (PDF). Astronomy and Astrophysics. 498 (3): 961. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.