天鵝座α型變星

天鵝座α型變星是顯示出非徑向脈動的變星，意味著當恆星表面有些地方收縮時，而同時也有些地方是擴張的^[1]。它們是光譜類型B或A的超巨星，亮度變化在0.1視星等，並與脈動相關聯，而由於和多脈動週期的節拍相關聯，因而通常是不規則變星。脈衝週期通常有幾天到幾個星期的周期。

這種變星的原型是天津四（天鵝座α），顯示的亮度在1.21 和 +1.29 之間波動。眾所周知很多在早期的超巨星都有小幅快速的變動，但之前它們未被歸為一類，直到1985年的變星總表第四版才收錄為變星的一種，縮寫的字母為ACYG（Alpha Cygni variable stars）^[2]。許多高光度藍變星（LBVs）在它們平靜（熱）階段顯示出天鵝座α型變星的型態，但在這種情況下一般仍使用LBV的分類。

克裡斯托費爾（Christoffel Waelkens）和他的同事在1998年的研究，分析依巴谷衛星的資料，發現了大量（32）此類變星^[3]。

脈動编辑

還不完全清楚天鵝座α型變星的脈動，它們並不限於窄幅的溫度和光度脈動星的方式。可以是最明亮的A和B超巨星，也可能是O和F的恆星，顯示某種不可預知的小規模（尺度）脈動類型。非絕熱過程的奇怪模式逕向脈動只顯現在最明亮的超巨星。通過假設它們是低質量的後紅超巨星，低明亮的超巨星也有脈動模式，但多數的天鵝座α型變星似乎未顯現經歷過紅巨星的階段^[4]^[5]。

賣有可能誘發κ機制，造成鐵不透明度的變化，產生觀測上奇怪的短週期逕向和非逕向脈動方式。非絕熱的G-模式可能會產生較長的週期變化，但這些均未在天鵝座α型變星上觀測到^[6]。

列表编辑

銀河系的编辑

名稱	星座	發現	最大視星等 (m_V)^[7]	最小視星等 (m_V)^[7]	週期（天）	光譜類型	發光度	註解
CE Cam (HD 21389)	鹿豹座	Percy & Welsh (1983)^[8]	4^m.54			A0Iab	63,000^[9]
CS Cam	鹿豹座		4^m.259			B9Ia
大犬座η（Aludra）	大犬座	Kazarovets et al. (1999)^[10]	2^m.38	2^m.48	4.70433	B5Ia	105,000^[9]
大犬座ο²	大犬座	Waelkens et al. (1998)^[3]	2^m.98	3^m.04	24.44	B3Ia	219,000^[11]
仙后座κ	仙后座	Percy & Welsh (1983)^[8]	4^m.12	4^m.21	2.64690	B1Ia	331,000^[11]
半人馬座ο²	半人馬座		5^m.12	5^m.22	46.3	A2Ia	136,000^[12]
仙王座ν	仙王座	Percy & Welsh (1983)^[8]	4^m.25	4^m.35		A2 Iab	254,000^[9]
南十字座DL	南十字座	Waelkens et al. (1998)^[3]	6^m.24	6^m.28	2.8778	B1.5Ia	242,000^[13]
天津四^[5]	天鵝座	Lee (1910)^[14]	1^m.21	1^m.29		A2 Ia	196,000^[15]	原型
天鵝座σ	天鵝座	Abt (1957)^[16]	4^m.19	4^m.26	120.2	B9 Iab	39,000^[17]
雙子座3	雙子座	Waelkens et al. (1998)^[3]	5^m.75		13.70	B3 Ia	200,000^[18]
獅子座ρ	獅子座	Olsen (1974)^[19]	3^m.83	3^m.9	3.4271	B1Iab	295,000^[11]
參宿七^[5]	獵戶座	Waelkens et al. (1998)^[3]	0^m.17	0^m.22	2.0748	B8Ia	279,000^[20] 218,000^[21]	Brightest member
ε Ori（Alnilam）	獵戶座	Cousins (1960)^[22]	1^m.64	1^m.74	2.0748	B0.5Iabea	275,000^[11] 537,000^[23]
獵戶座χ²（Rigel）	獵戶座	Waelkens et al. (1998)^[3]	4^m.68	4^m.72	2.8682	B2Ia	446,000^[11]

其他星系编辑

名稱	星系	最大視星等 (m_V)	最小視星等 (m_V)	週期（天）	光譜類型	註解
LHA 115-S 18^[24]	SMC	13^m.3		複雜的	B[e]sg	可能是LBV
HDE 268835^[24]	LMC	10^m.60	10^m.68	>100	B8p
HD 37974^[24]	LMC	10^m.92	11^m.00	400	B0.5Ia⁺

參考資料编辑

^ Nonradial Pulsation. Universität Wien. [2010-02-22]. （原始内容存档于2009-10-24）.
^ Kholopov, P. N.; Samus', N. N.; Frolov, M. S.; Goranskij, V. P.; Gorynya, N. A.; Kireeva, N. N.; Kukarkina, N. P.; Kurochkin, N. E.; Medvedeva, G. I.; Perova, N. B. VizieR Online Data Catalog: General Catalog of Variable Stars, 4th Ed. (GCVS4) (Kholopov+ 1988). VizieR On-line Data Catalog: II/139B. Originally published in: Moscow: Nauka Publishing House (1985-1988). 1996, 2139: 0. Bibcode:1996yCat.2139....0K.
^ ^3.0 ^3.1 ^3.2 ^3.3 ^3.4 ^3.5 Waelkens, C.; Aerts, C.; Kestens, E.; Grenon, M.; Eyer, L. Study of an unbiased sample of B stars observed with Hipparcos: the discovery of a large amount of new slowly pulsating B star. Astronomy and Astrophysics. 1998, 330: 215–21. Bibcode:1998A&A...330..215W.
^ Saio, H.; Georgy, C.; Meynet, G. Strange-Mode Instability for Micro-Variations in Luminous Blue Variables. Progress in Physics of the Sun and Stars: A New Era in Helio- and Asteroseismology. Proceedings of a Fujihara Seminar held 25–29 November. Astronomical Society of the Pacific Conference Series 479. 2013: 47. Bibcode:2013ASPC..479...47S. arXiv:1305.4728  .
^ ^5.0 ^5.1 ^5.2 Saio, H.; Georgy, C.; Meynet, G. Evolution of blue supergiants and Cygni variables: puzzling CNO surface abundances. Monthly Notices of the Royal Astronomical Society. 2013, 433 (2): 1246–1257. Bibcode:2013MNRAS.433.1246S. arXiv:1305.2474  . doi:10.1093/mnras/stt796.
^ Saio, Hideyuki. Linear analyses for the stability of radial and non-radial oscillations of massive stars. Monthly Notices of the Royal Astronomical Society. 2011, 412 (3): 1814–1822. Bibcode:2011MNRAS.412.1814S. ISSN 0035-8711. arXiv:1011.4729  . doi:10.1111/j.1365-2966.2010.18019.x.
^ ^7.0 ^7.1 Samus, N. N.; Durlevich, O. V.; et al. VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013). VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 2009, 1: 02025. Bibcode:2009yCat....102025S.
^ ^8.0 ^8.1 ^8.2 Percy, J. R.; Welch, D. L. Photometric variability of B- and A-type supergiants. Publications of the Astronomical Society of the Pacific. 1983, 95: 491. Bibcode:1983PASP...95..491P. ISSN 0004-6280. doi:10.1086/131198.
^ ^9.0 ^9.1 ^9.2 Hohle, M. M.; Neuhäuser, R.; Schutz, B. F., Masses and luminosities of O- and B-type stars and red supergiants, Astronomische Nachrichten, April 2010, 331 (4): 349, Bibcode:2010AN....331..349H, arXiv:1003.2335  , doi:10.1002/asna.200911355
^ Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. The 74th Special Name-list of Variable Stars. Information Bulletin on Variable Stars. 1999, 4659: 1. Bibcode:1999IBVS.4659....1K.
^ ^11.0 ^11.1 ^11.2 ^11.3 ^11.4 Crowther, P. A.; Lennon, D. J.; Walborn, N. R. Physical parameters and wind properties of galactic early B supergiants. Astronomy and Astrophysics. 2006, 446: 279. Bibcode:2006A&A...446..279C. arXiv:astro-ph/0509436  . doi:10.1051/0004-6361:20053685.
^ Kaufer, A.; Stahl, O.; Wolf, B.; Gaeng, T.; Gummersbach, C. A.; Kovacs, J.; Mandel, H.; Szeifert, T. Long-term spectroscopic monitoring of BA-type supergiants. I. Halpha_ line-profile variability.. Astronomy and Astrophysics. 1996, 305: 887–901. Bibcode:1996A&A...305..887K.
^ Lamers, Henny J. G. L. M.; Snow, Theodore P.; Lindholm, Douglas M. Terminal Velocities and the Bistability of Stellar Winds. The Astrophysical Journal. 1995, 455: 269. Bibcode:1995ApJ...455..269L. ISSN 0004-637X. doi:10.1086/176575.
^ Lee, O. J. Four stars having variable radial velocities.. The Astrophysical Journal. 1910, 31: 176. Bibcode:1910ApJ....31..176L. ISSN 0004-637X. doi:10.1086/141741.
^ Schiller, F.; Przybilla, N. Quantitative spectroscopy of Deneb. Astronomy & Astrophysics. 2008, 479 (3): 849–858. Bibcode:2008A&A...479..849S. arXiv:0712.0040  . doi:10.1051/0004-6361:20078590.
^ Abt, Helmut A. The Variability of Supergiants.. The Astrophysical Journal. 1957, 126: 138. Bibcode:1957ApJ...126..138A. ISSN 0004-637X. doi:10.1086/146379.
^ Markova, N.; Puls, J. Bright OB stars in the Galaxy. Astronomy and Astrophysics. 2008, 478 (3): 823–842. Bibcode:2008A&A...478..823M. ISSN 0004-6361. arXiv:0711.1110  . doi:10.1051/0004-6361:20077919.
^ Kudritzki, R. P.; Puls, J.; Lennon, D. J.; Venn, K. A.; Reetz, J.; Najarro, F.; McCarthy, J. K.; Herrero, A. The wind momentum-luminosity relationship of galactic A- and B-supergiants. Astronomy and Astrophysics. 1999, 350: 970. Bibcode:1999A&A...350..970K. arXiv:astro-ph/9910449  .
^ Olsen, E. H. Variable Stars among the Four-Colour (uvby) Standard Stars. Information Bulletin on Variable Stars. 1974, 925: 1. Bibcode:1974IBVS..925....1O.
^ Chesneau, O.; Kaufer, A.; Stahl, O.; Colvinter, C.; Spang, A.; Dessart, L.; Prinja, R.; Chini, R. The variable stellar wind of Rigel probed at high spatial and spectral resolution. Astronomy & Astrophysics. 2014, 566: 18. Bibcode:2014A&A...566A.125C. arXiv:1405.0907  . doi:10.1051/0004-6361/201322894. A125.
^ Przybilla, N.; et al. Quantitative spectroscopy of BA-type supergiants. Astronomy and Astrophysics. January 2006, 445 (3): 1099–1126. Bibcode:2006A&A...445.1099P. arXiv:astro-ph/0509669  . doi:10.1051/0004-6361:20053832.
^ Cousins, A. W. J. New Bright Variable Stars. Monthly Notes of the Astron. Soc. Southern Africa. 1960, 19: 56. Bibcode:1960MNSSA..19...56C.
^ Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters. Astronomy and Astrophysics. 2008, 481 (3): 777–97. Bibcode:2008A&A...481..777S. arXiv:0801.4289  . doi:10.1051/0004-6361:20077125.
^ ^24.0 ^24.1 ^24.2 van Genderen, A. M.; Sterken, C. Light variations of massive stars (α Cyg variables). Astronomy and Astrophysics. 2002, 386 (3): 926–935. Bibcode:2002A&A...386..926V. doi:10.1051/0004-6361:20020360.

Samus N.N., Durlevich O.V., et al. Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.)

[1] Nonradial Pulsation. Universität Wien. [2010-02-22]. （原始内容存档于2009-10-24）.

[2] Kholopov, P. N.; Samus', N. N.; Frolov, M. S.; Goranskij, V. P.; Gorynya, N. A.; Kireeva, N. N.; Kukarkina, N. P.; Kurochkin, N. E.; Medvedeva, G. I.; Perova, N. B. VizieR Online Data Catalog: General Catalog of Variable Stars, 4th Ed. (GCVS4) (Kholopov+ 1988). VizieR On-line Data Catalog: II/139B. Originally published in: Moscow: Nauka Publishing House (1985-1988). 1996, 2139: 0. Bibcode:1996yCat.2139....0K.

[waelkens_1998-3] 3.0 ^3.1 ^3.2 ^3.3 ^3.4 ^3.5 Waelkens, C.; Aerts, C.; Kestens, E.; Grenon, M.; Eyer, L. Study of an unbiased sample of B stars observed with Hipparcos: the discovery of a large amount of new slowly pulsating B star. Astronomy and Astrophysics. 1998, 330: 215–21. Bibcode:1998A&A...330..215W.

[saio-4] Saio, H.; Georgy, C.; Meynet, G. Strange-Mode Instability for Micro-Variations in Luminous Blue Variables. Progress in Physics of the Sun and Stars: A New Era in Helio- and Asteroseismology. Proceedings of a Fujihara Seminar held 25–29 November. Astronomical Society of the Pacific Conference Series 479. 2013: 47. Bibcode:2013ASPC..479...47S. arXiv:1305.4728  .

[SaioGeorgy2013-5] 5.0 ^5.1 ^5.2 Saio, H.; Georgy, C.; Meynet, G. Evolution of blue supergiants and Cygni variables: puzzling CNO surface abundances. Monthly Notices of the Royal Astronomical Society. 2013, 433 (2): 1246–1257. Bibcode:2013MNRAS.433.1246S. arXiv:1305.2474  . doi:10.1093/mnras/stt796.

[Saio2011-6] Saio, Hideyuki. Linear analyses for the stability of radial and non-radial oscillations of massive stars. Monthly Notices of the Royal Astronomical Society. 2011, 412 (3): 1814–1822. Bibcode:2011MNRAS.412.1814S. ISSN 0035-8711. arXiv:1011.4729  . doi:10.1111/j.1365-2966.2010.18019.x.

[gcvs-7] 7.0 ^7.1 Samus, N. N.; Durlevich, O. V.; et al. VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013). VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 2009, 1: 02025. Bibcode:2009yCat....102025S.

[PercyWelch1983-8] 8.0 ^8.1 ^8.2 Percy, J. R.; Welch, D. L. Photometric variability of B- and A-type supergiants. Publications of the Astronomical Society of the Pacific. 1983, 95: 491. Bibcode:1983PASP...95..491P. ISSN 0004-6280. doi:10.1086/131198.

[an331_4_349-9] 9.0 ^9.1 ^9.2 Hohle, M. M.; Neuhäuser, R.; Schutz, B. F., Masses and luminosities of O- and B-type stars and red supergiants, Astronomische Nachrichten, April 2010, 331 (4): 349, Bibcode:2010AN....331..349H, arXiv:1003.2335  , doi:10.1002/asna.200911355

[10] Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. The 74th Special Name-list of Variable Stars. Information Bulletin on Variable Stars. 1999, 4659: 1. Bibcode:1999IBVS.4659....1K.

[crowther-11] 11.0 ^11.1 ^11.2 ^11.3 ^11.4 Crowther, P. A.; Lennon, D. J.; Walborn, N. R. Physical parameters and wind properties of galactic early B supergiants. Astronomy and Astrophysics. 2006, 446: 279. Bibcode:2006A&A...446..279C. arXiv:astro-ph/0509436  . doi:10.1051/0004-6361:20053685.

[Kaufer_1996-12] Kaufer, A.; Stahl, O.; Wolf, B.; Gaeng, T.; Gummersbach, C. A.; Kovacs, J.; Mandel, H.; Szeifert, T. Long-term spectroscopic monitoring of BA-type supergiants. I. Halpha_ line-profile variability.. Astronomy and Astrophysics. 1996, 305: 887–901. Bibcode:1996A&A...305..887K.

[lamers1995-13] Lamers, Henny J. G. L. M.; Snow, Theodore P.; Lindholm, Douglas M. Terminal Velocities and the Bistability of Stellar Winds. The Astrophysical Journal. 1995, 455: 269. Bibcode:1995ApJ...455..269L. ISSN 0004-637X. doi:10.1086/176575.

[Lee1910-14] Lee, O. J. Four stars having variable radial velocities.. The Astrophysical Journal. 1910, 31: 176. Bibcode:1910ApJ....31..176L. ISSN 0004-637X. doi:10.1086/141741.

[schiller-15] Schiller, F.; Przybilla, N. Quantitative spectroscopy of Deneb. Astronomy & Astrophysics. 2008, 479 (3): 849–858. Bibcode:2008A&A...479..849S. arXiv:0712.0040  . doi:10.1051/0004-6361:20078590.

[Abt1957-16] Abt, Helmut A. The Variability of Supergiants.. The Astrophysical Journal. 1957, 126: 138. Bibcode:1957ApJ...126..138A. ISSN 0004-637X. doi:10.1086/146379.

[MarkovaPuls2008-17] Markova, N.; Puls, J. Bright OB stars in the Galaxy. Astronomy and Astrophysics. 2008, 478 (3): 823–842. Bibcode:2008A&A...478..823M. ISSN 0004-6361. arXiv:0711.1110  . doi:10.1051/0004-6361:20077919.

[18] Kudritzki, R. P.; Puls, J.; Lennon, D. J.; Venn, K. A.; Reetz, J.; Najarro, F.; McCarthy, J. K.; Herrero, A. The wind momentum-luminosity relationship of galactic A- and B-supergiants. Astronomy and Astrophysics. 1999, 350: 970. Bibcode:1999A&A...350..970K. arXiv:astro-ph/9910449  .

[olsen-19] Olsen, E. H. Variable Stars among the Four-Colour (uvby) Standard Stars. Information Bulletin on Variable Stars. 1974, 925: 1. Bibcode:1974IBVS..925....1O.

[Chesneau_2014-20] Chesneau, O.; Kaufer, A.; Stahl, O.; Colvinter, C.; Spang, A.; Dessart, L.; Prinja, R.; Chini, R. The variable stellar wind of Rigel probed at high spatial and spectral resolution. Astronomy & Astrophysics. 2014, 566: 18. Bibcode:2014A&A...566A.125C. arXiv:1405.0907  . doi:10.1051/0004-6361/201322894. A125.

[aaa445_3_1099-21] Przybilla, N.; et al. Quantitative spectroscopy of BA-type supergiants. Astronomy and Astrophysics. January 2006, 445 (3): 1099–1126. Bibcode:2006A&A...445.1099P. arXiv:astro-ph/0509669  . doi:10.1051/0004-6361:20053832.

[cousins-22] Cousins, A. W. J. New Bright Variable Stars. Monthly Notes of the Astron. Soc. Southern Africa. 1960, 19: 56. Bibcode:1960MNSSA..19...56C.

[Searle_2008-23] Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters. Astronomy and Astrophysics. 2008, 481 (3): 777–97. Bibcode:2008A&A...481..777S. arXiv:0801.4289  . doi:10.1051/0004-6361:20077125.

[vanGenderenSterken2002-24] 24.0 ^24.1 ^24.2 van Genderen, A. M.; Sterken, C. Light variations of massive stars (α Cyg variables). Astronomy and Astrophysics. 2002, 386 (3): 926–935. Bibcode:2002A&A...386..926V. doi:10.1051/0004-6361:20020360.

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[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

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