Astronomy:Helium-weak star
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Helium-weak stars are chemically peculiar stars which have a weak helium lines for their spectral type.[1][2] Their helium lines place them in a later (i.e. cooler) spectral type then their hydrogen lines.[3]
List of helium-weak stars
This is a non-extensive list of helium-weak stars.[4][5]
Star Name | Constellation | Apparent Magnitude (mv) | Class | Notes |
---|---|---|---|---|
20 Eridani (EG Eridani) | Eridanus | 5.23 | B8/9 III | α2 CVn variable |
30 Capricorni | Capricornus | 5.38 | B5 II/III | |
θ Hydri | Hydrus | 5.50 | bgcolor="Template:Color temperature"| B8 III/IV | Suspected Binary; |
22 Eridani (FY Eridani) | Eridanus | 5.53 | B9 IIIpSi (4200) | α2 CVn variable |
HD 74196 | Vela | 5.61 | B7 Vn | Part of IC 2391 |
HD 28843 (DZ Eridani) | Eridanus | 5.81 | bgcolor="Template:Color temperature"| B9 III | SX Arietis variable |
12 Canis Majoris (HK Canis Majoris) | Canis Major | 6.08 | bgcolor="Template:Color temperature"| B7 II/III | SX Arietis variable |
HD 34797 (TX Leporis) | Lepus | 6.54 | B7 Vp | α2 CVn variable; binary |
HD 35456 | Orion | 6.95 | B9 II/III | Binary |
Helium-strong star
A related class of stars have anomalously strong helium lines in their spectra, and are known as helium-strong stars.[1]
See also
References
- ↑ 1.0 1.1 Landstreet, J. D.; Bohlender, David A. (1988). "Abundance and Magnetic Field Geometries of Helium-Strong and Helium-Weak Stars" (in en). Symposium - International Astronomical Union 132: 309–312. doi:10.1017/S0074180900035191. ISSN 0074-1809. Bibcode: 1987BAAS...19..704B.
- ↑ Preston, George W. (1974). "The Chemically Peculiar Stars of the Upper Main Sequence". Annual Review of Astronomy and Astrophysics 12 (1): 257–277. doi:10.1146/annurev.aa.12.090174.001353. Bibcode: 1974ARA&A..12..257P.
- ↑ "A Digital Spectral Classification Atlas - R. O. Gray". https://ned.ipac.caltech.edu/level5/Gray/Gray9.html.
- ↑ Jaschek, Mercedes; Jaschek, Carlos; Arnal, Marcelo (October 1969). "Helium-Weak Stars". Publications of the Astronomical Society of the Pacific 81 (482): 651. doi:10.1086/128832. Bibcode: 1969PASP...81..650J.
- ↑ Alonso, M. S.; López-García, Z.; Malaroda, S.; Leone, F. (April 2003). "Elemental abundance studies of CP stars. The helium-weak stars HD 19400, HD 34797 and HD 35456*". Astronomy and Astrophysics 402: 331. doi:10.1051/0004-6361:20030222. Bibcode: 2003A&A...402..331A.
Original source: https://en.wikipedia.org/wiki/Helium-weak star.
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