R136b

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R136b
The young cluster R136.jpg
R136b is the bright star towards the lower left.
Credit: ESO
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Dorado
Right ascension 05h 38m 42.74s[1]
Declination −69° 06′ 03.78″[1]
Apparent magnitude (V) 13.24[1]
Characteristics
Spectral type O4If/WN8[2]
B−V color index −0.18[1]
Astrometry
Distance 163,000 ly
(49,970[3] pc)
Absolute magnitude (MV) −7.31[2]
Details[2]
Mass 93 M
Radius 22.3[4] R
Luminosity 1,995,000 L
Temperature 41,000 K
Age 1.5 Myr
Other designations
BAT99 111, RMC 136b, [HSH95] 9, [WO84] 4, NGC 2070 MH 637, [CHH92] 26, [P93] 985.
Database references
SIMBAD data

R136b is a Wolf-Rayet star in the R136 cluster in the Large Magellanic Cloud.[4] It is one of the most massive and most luminous stars known. It is found in the dense R136 open cluster at the centre of NGC 2070 in the Tarantula Nebula.

R136b has a transitional spectral type between an O class supergiant and a Wolf-Rayet star, with a mix of absorption and emission lines. Although it shows enhanced helium and nitrogen at its surface, it is still a very young star, still burning hydrogen in its core via the CNO cycle, and still effectively a main sequence object.[5]

References[edit]

  1. ^ a b c d Doran, E. I.; Crowther, P. A.; De Koter, A.; Evans, C. J.; McEvoy, C.; Walborn, N. R.; Bastian, N.; Bestenlehner, J. M.; Gräfener, G.; Herrero, A.; Köhler, K.; Maíz Apellániz, J.; Najarro, F.; Puls, J.; Sana, H.; Schneider, F. R. N.; Taylor, W. D.; Van Loon, J. Th.; Vink, J. S. (2013). "The VLT-FLAMES Tarantula Survey. XI. A census of the hot luminous stars and their feedback in 30 Doradus". Astronomy & Astrophysics. 558: A134. arXiv:1308.3412Freely accessible. Bibcode:2013A&A...558A.134D. doi:10.1051/0004-6361/201321824. 
  2. ^ a b c Crowther, Paul A.; Caballero-Nieves, S. M.; Bostroem, K. A.; Maíz Apellániz, J.; Schneider, F. R. N.; Walborn, N. R.; Angus, C. R.; Brott, I.; Bonanos, A.; De Koter, A.; De Mink, S. E.; Evans, C. J.; Gräfener, G.; Herrero, A.; Howarth, I. D.; Langer, N.; Lennon, D. J.; Puls, J.; Sana, H.; Vink, J. S. (2016). "The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He II λ1640 in young star clusters". Monthly Notices of the Royal Astronomical Society. 458: 624. arXiv:1603.04994Freely accessible. Bibcode:2016MNRAS.458..624C. doi:10.1093/mnras/stw273. 
  3. ^ Pietrzyński, G; D. Graczyk; W. Gieren; I. B. Thompson; B. Pilecki; A. Udalski; I. Soszyński; et al. (7 March 2013). "An eclipsing-binary distance to the Large Magellanic Cloud accurate to two per cent". Nature. 495 (7439): 76–79. arXiv:1303.2063Freely accessible. Bibcode:2013Natur.495...76P. doi:10.1038/nature11878. PMID 23467166. 
  4. ^ a b Hainich, R.; Rühling, U.; Todt, H.; Oskinova, L. M.; Liermann, A.; Gräfener, G.; Foellmi, C.; Schnurr, O.; Hamann, W. -R. (2014). "The Wolf-Rayet stars in the Large Magellanic Cloud". Astronomy & Astrophysics. 565: A27. arXiv:1401.5474Freely accessible. Bibcode:2014A&A...565A..27H. doi:10.1051/0004-6361/201322696. 
  5. ^ Crowther, Paul A.; Schnurr, Olivier; Hirschi, Raphael; Yusof, Norhasliza; Parker, Richard J.; Goodwin, Simon P.; Kassim, Hasan Abu (2010). "The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150Msolar stellar mass limit". Monthly Notices of the Royal Astronomical Society. 408 (2): 731. arXiv:1007.3284Freely accessible. Bibcode:2010MNRAS.408..731C. doi:10.1111/j.1365-2966.2010.17167.x.