Nu Pavonis

Not to be confused with NU Pavonis.
Nu Pavonis
Location of 𝜈 Pavonis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Pavo
Right ascension 18h 31m 22.42509s[1]
Declination −62° 16′ 41.8853″[1]
Apparent magnitude (V) 4.64 (4.60 - 4.64[2])
Characteristics
Evolutionary stage main sequence[3]
Spectral type B7III[4]
U−B color index −0.39[5]
B−V color index −0.11[5]
Variable type SPB[2]
Astrometry
Radial velocity (Rv)+16.95[6] km/s
Proper motion (ÎŒ) RA: âˆ’1.11[1] mas/yr
Dec.: âˆ’45.31[1] mas/yr
Parallax (π)7.43 Â± 0.24 mas[1]
Distance440 ± 10 ly
(135 ± 4 pc)
Absolute magnitude (MV)-1.01[4]
Orbit[7]
Period (P)1.711529±0.000005 d
Eccentricity (e)0.0
Periastron epoch (T)2,450,276.5502±0.0007 HJD
Argument of periastron (ω)
(secondary)		127±12°
Semi-amplitude (K1)
(primary)		43.8±0.1 km/s
Details
Mass4.39[8] M☉
Luminosity659[8] L☉
Temperature12,764[8] K
Rotational velocity (v sin i)125.0[9] km/s
Other designations
Îœ Pav, CD−62°1213, GC 25227, HD 169978, HIP 90797, HR 6916, SAO 254273, WDS J18314-6217AB[10]
Database references
SIMBADdata

Nu Pavonis is a possible triple star system[11] in the southern constellation of Pavo. It is visible to the naked eye as a faint star that varies in apparent visual magnitude from 4.60 to 4.64 over a period of 0.85584 days.[2] The system lies approximately 440 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +17 km/s.[6] It is a possible member of the Wolf 630 group of co-moving stars.[3]

A light curve for Nu Pavonis, plotted from TESS data[12]

This is a single-lined spectroscopic binary system with an orbital period of just 1.71 days in a circular orbit.[7] The unresolved[3] components are close enough that their tidal interaction is significant.[7] The visible component is a slowly pulsating B-type star with a stellar classification of B7III.[4] This implies it is an evolved giant star, but it is actually more likely to be on the main sequence. An X-ray emission has been detected from the pair.[3]

The third component is a visible companion, probably a pre-main-sequence star, at magnitude 13.7 and separation 3.1″. This star is estimated at 0.15 solar masses and an effective temperature of 3,192 K.[8] It too is an X-ray source.[3]

References

  1. ^ a b c d e f Van Leeuwen, F. (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. S2CID 18759600. Vizier catalog entry
  2. ^ a b c Watson, C. L. (2006). "The International Variable Star Index (VSX)". The Society for Astronomical Sciences 25th Annual Symposium on Telescope Science. Held May 23–25. 25: 47. Bibcode:2006SASS...25...47W.
  3. ^ a b c d e Stelzer, B.; et al. (September 2003). "Late B-type stars and their candidate companions resolved with Chandra". Astronomy and Astrophysics. 407 (3): 1067–1078. arXiv:astro-ph/0306401. Bibcode:2003A&A...407.1067S. doi:10.1051/0004-6361:20030934. S2CID 16766165.
  4. ^ 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. S2CID 119257644. Vizier catalog entry
  5. ^ a b Ducati, J. R. (2002). "VizieR On-Line Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  6. ^ a b Pourbaix, D.; et al. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics. 424 (2): 727–732. arXiv:astro-ph/0406573. Bibcode:2004A&A...424..727P. doi:10.1051/0004-6361:20041213. S2CID 119387088.
  7. ^ a b c De Cat, P.; Aerts, C.; De Ridder, J.; Kolenberg, K.; Meeus, G.; Decin, L. (2000). "A study of bright southern slowly pulsating B stars. I. Determination of the orbital parameters and of the main frequency of the spectroscopic binaries". Astronomy and Astrophysics. 355: 1015–1030. Bibcode:2000A&A...355.1015D.
  8. ^ a b c d Hubrig, S.; Le Mignant, D.; North, P.; Krautter, J. (2001). "Search for low-mass PMS companions around X-ray selected late B stars". Astronomy and Astrophysics. 372: 152–164. arXiv:astro-ph/0103201. Bibcode:2001A&A...372..152H. doi:10.1051/0004-6361:20010452. S2CID 17507782.
  9. ^ Glebocki, R.; Gnacinski, P. (2005). "Catalog of Stellar Rotational Velocities". VizieR On-Line Data Catalog: III/244. 3244. Bibcode:2005yCat.3244....0G. Vizier catalog entry
  10. ^ "nu. Pav". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-01.
  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. S2CID 14878976.
  12. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 24 September 2022.