V518 Carinae (HR 4196) is a naked-eye variable star in the constellation Carina. It is a member of the bright open cluster IC 2602 near the Carina Nebula.

V518 Carinae
Location of V518 Carinae in IC 2602 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Carina
Right ascension 10h 42m 14.12040s[1]
Declination −64° 27′ 59.1323″[1]
Apparent magnitude (V) 4.82[2]
Characteristics
Spectral type B3/5V[3]
U−B color index −0.58[2]
B−V color index −0.14[2]
Variable type γ Cas?[4]
Astrometry
Parallax (π)7.19 ± 0.20 mas[1]
Distance450 ± 10 ly
(139 ± 4 pc)
Absolute magnitude (MV)−1.169[5]
Details
Mass6.2[6] M
Radius3.30±0.07[7] R
Luminosity753[5] L
Surface gravity (log g)4.015[8] cgs
Temperature15,397[5] K
Rotational velocity (v sin i)120[8] km/s
Age17.2[9] Myr
Other designations
V518 Carinae, HD 92938, HIP 52370, HR 4196
Database references
SIMBADdata

Location

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V518 Carinae lies in the open cluster IC 2602, 5 arc minutes from its brightest member θ Carinae.

Variability

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A light curve for V518 Carinae, plotted from Hipparcos data[10]

518 Carinae was discovered to change in brightness after analysis of Hipparcos photometry. The amplitude of the variations seen is 0.2 magnitudes, with possible periods of 100 and 971 days.[11] It is classified as a γ Cassiopeiae variable.[12][4]

Spectral peculiarities

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V518 Carinae is classified as a B-type main sequence star between B3 and B5.[13] It is also catalogued as a helium star, a chemically peculiar star with abnormally strong helium absorption lines in its spectrum and relatively weak hydrogen lines. It is possibly a blue straggler.[14]

V518 Carinae is also a Be star, a hot star with emission lines in its spectrum due to a disk of material around the star. Be stars that show irregular brightness changes due to the disk are grouped as γ Cassiopeiae variables. V518 Carinae is known to produce disk outbursts lasting several hundred days.[15]

References

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  1. ^ a b c 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.
  2. ^ a b c Ducati, J. R (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ Houk, N; Cowley, A. P (1975). "University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0". University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
  4. ^ a b Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
  5. ^ a b c Silaj, J; Landstreet, J. D (2014). "Accurate age determinations of several nearby open clusters containing magnetic Ap stars". Astronomy & Astrophysics. 566: A132. arXiv:1407.4531. Bibcode:2014A&A...566A.132S. doi:10.1051/0004-6361/201321468. S2CID 53370832.
  6. ^ Tetzlaff, N; Neuhäuser, R; Hohle, M. M (2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. S2CID 118629873.
  7. ^ Arcos, C.; et al. (March 2018). "Stellar parameters and H α line profile variability of Be stars in the BeSOS survey". Monthly Notices of the Royal Astronomical Society. 474 (4): 5287–5299. arXiv:1711.08675. Bibcode:2018MNRAS.474.5287A. doi:10.1093/mnras/stx3075. S2CID 74872624.
  8. ^ a b David, Trevor J; Hillenbrand, Lynne A (2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607.
  9. ^ Gullikson, Kevin; Dodson-Robinson, Sarah (2013). "Detection of Low-Mass-ratio Stellar Binary Systems". The Astronomical Journal. 145 (1): 3. arXiv:1210.6360. Bibcode:2013AJ....145....3G. doi:10.1088/0004-6256/145/1/3. S2CID 118517725.
  10. ^ "Hipparcos Tools Interactive Data Access". Hipparcos. ESA. Retrieved 8 December 2021.
  11. ^ Lefèvre, L; Marchenko, S. V; Moffat, A. F. J; Acker, A (2009). "A systematic study of variability among OB-stars based on HIPPARCOS photometry". Astronomy and Astrophysics. 507 (2): 1141. Bibcode:2009A&A...507.1141L. doi:10.1051/0004-6361/200912304.
  12. ^ Adelman, S. J; Mayer, M. R; Rosidivito, M. A (2000). "On the Variability of O4-B5 Luminosity Class III-V Stars". Information Bulletin on Variable Stars. 5008: 1. Bibcode:2000IBVS.5008....1A.
  13. ^ Skiff, B. A (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2016)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014). 1. Bibcode:2014yCat....1.2023S.
  14. ^ Renson, P; Manfroid, J (2009). "Catalogue of Ap, Hg Mn and Am stars". Astronomy and Astrophysics. 498 (3): 961. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.
  15. ^ Mennickent, R. E; Sabogal, B; Granada, A; Cidale, L (2009). "L-Band Spectra of 13 Outbursting Be Stars". Publications of the Astronomical Society of the Pacific. 121 (876): 125. arXiv:0902.4279. Bibcode:2009PASP..121..125M. doi:10.1086/597551. S2CID 119286005.