PV Telescopii
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 18h 23m 14.66390s[1] |
| Declination | −56° 37′ 44.1512″[1] |
| Apparent magnitude (V) | 9.30[2] |
| Characteristics | |
| Spectral type | B5p[3] |
| U−B color index | −0.60[2] |
| B−V color index | −0.10[2] |
| Variable type | PV Tel |
| Astrometry | |
| Radial velocity (Rv) | -169[4] km/s |
| Proper motion (μ) | RA: 0.38[1] mas/yr Dec.: -9.29[1] mas/yr |
| Parallax (π) | 0.43 ± 1.12[1] mas |
| Distance | 8,000[5] pc |
| Absolute magnitude (MV) | −4.4[6] |
| Details | |
| Mass | 0.94[5] M☉ |
| Radius | 33.9[5] R☉ |
| Luminosity | 25,000[5] L☉ |
| Surface gravity (log g) | 1.35[5] cgs |
| Temperature | 12,425[5] K |
| Metallicity | -0.15[7] |
| Other designations | |
| Database references | |
| SIMBAD | data |
PV Telescopii (also known as HD 168476) is a class B-type (blue) extreme helium star in the constellation Telescopium. It is also the prototype of variable stars called PV Telescopii variables. These are probably post-AGB stars with weak hydrogen lines and enhanced helium and carbon lines. Their variable periods are from a few hours to a few years and as of 2008, there are 12 confirmed PV Telescopii variables. Some researchers have modelled white dwarf mergers as a way to produce these unlikely stars.[8]
References
- 1 2 3 4 5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- 1 2 3 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.
- ↑ Walker, H. J.; Hill, P. W. (1985). "Radial velocities for the hydrogen-deficient star HD 168476, several helium-strong and helium-weak stars". Astronomy and Astrophysics Supplement Series (ISSN 0365-0138) 61: 303. Bibcode:1985A&AS...61..303W.
- ↑ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
- 1 2 3 4 5 6 Jeffery, C. S.; Starling, R. L. C.; Hill, P. W.; Pollacco, D. (2001). "Cyclic and secular variation in the temperatures and radii of extreme helium stars". Monthly Notices of the Royal Astronomical Society 321: 111. Bibcode:2001MNRAS.321..111J. doi:10.1046/j.1365-8711.2001.03992.x.
- ↑ Heber, U.; Schoenberner, D. (1981). "Colours and effective temperatures of extreme helium stars". Astronomy and Astrophysics 102: 73. Bibcode:1981A&A...102...73H.
- ↑ Soubiran, C.; Le Campion, J. -F.; Cayrel De Strobel, G.; Caillo, A. (2010). "The PASTEL catalogue of stellar parameters". Astronomy and Astrophysics 515: A111. Bibcode:2010A&A...515A.111S. doi:10.1051/0004-6361/201014247.
- ↑ Gourgouliatos, K. N.; Jeffery, C. S. (2006). "On the angular momentum evolution of merged white dwarfs". Monthly Notices of the Royal Astronomical Society 371 (3): 1381. Bibcode:2006MNRAS.371.1381G. doi:10.1111/j.1365-2966.2006.10780.x.
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