BZ Crucis
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| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Crux |
| Right ascension | 12h 42m 50.2656s[1] |
| Declination | −63° 03′ 31.048″[1] |
| Apparent magnitude (V) | 5.316[2] |
| Characteristics | |
| Spectral type | B1IVe[3] |
| U−B color index | −0.82[4] |
| B−V color index | +0.27[4] |
| Variable type | γ Cas |
| Astrometry | |
| Radial velocity (Rv) | +35[5] km/s |
| Proper motion (μ) | RA: −13.32 mas/yr Dec.: −3.47 mas/yr |
| Parallax (π) | 3.32 ± 0.56[1] mas |
| Distance | approx. 1,000 ly (approx. 300 pc) |
| Details | |
| Mass | 9.6[3] M☉ |
| Surface gravity (log g) | 3.5–3.9[3] cgs |
| Temperature | 22,510–25,000[3] K |
| Rotational velocity (v sin i) | 300–400[3] km/s |
| Other designations | |
BZ Crucis is a Be star in the constellation Crux, behind the southern Coalsack Nebula. It has a stellar classification of B1IVe, which means it is a subgiant star of class B that displays emission lines in its spectrum. This is a variable star of the Gamma Cassiopeiae type, indicating it is a shell star with a circumstellar disk of gas about the equator. It is not known to be a member of a binary system, although it is probably a member of the open cluster NGC 4609. This star is moderately luminous in the X-ray band, with a variable energy emission of 1032–33 erg s−1 in the range 0.2−12 keV. The X-ray emission may be caused by magnetic activity, or possibly by accretion onto a white dwarf companion.[3]
References
- ↑ 1.0 1.1 1.2 Perryman, M. A. C.; et al. (April 1997). "The HIPPARCOS Catalogue". Astronomy & Astrophysics 323: L49–L52. Bibcode:1997A&A...323L..49P.
- ↑ 2.0 2.1 "HR 4830 -- Be Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-12-09.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Lopes de Oliveira, R.; et al. (November 2007). "On the X-ray and optical properties of the Be star HD 110432: a very hard-thermal X-ray emitter". Astronomy and Astrophysics 474 (3): 983–996. arXiv:astro-ph/0701767. Bibcode:2007A&A...474..983L. doi:10.1051/0004-6361:20077295.
- ↑ 4.0 4.1 Cousins, A. W. J. (1973). "UBV photometry of some southern stars". Monthly Notes of the Astronomical Society of Southern Africa 32: 11. Bibcode:1973MNSSA..32...11C.
- ↑ Evans, D. S. (June 20–24, 1966). "The Revision of the General Catalogue of Radial Velocities". In Batten, Alan Henry; Heard, John Frederick. Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. University of Toronto: International Astronomical Union. Retrieved 2009-09-10.
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