zh %E5%A4%A7%E7%8A%AC%E5%BA%A7EZ

**EZ Canis Majoris**
	大犬座EZ的位置（紅圈）
觀測資料; 曆元 J2000.0
星座	大犬座
星官
赤經	06h 54m 13.04410s
赤緯	−23° 55′ 42.0150″
視星等（V）	6.91 6.71 to 6.95
特性
光谱分类	WN4-s
U−B 色指数	−0.89
B−V 色指数	−0.28
变星类型	UGZ?
天体测定
自行 (μ)	赤经：−4.431±0.057 mas/yr ; 赤纬：2.884±0.092 mas/yr
视差 (π)	0.4119 ± 0.0503 mas
距离	4,900 ly ; (1,500 pc)
绝对星等 (MV)	−5.33
	軌道
繞行週期 (P)	3.63 d
半長軸 (a)	0.13 au
偏心率 (e)	0.10
倾斜角 (i)	74°
詳細資料
WR
質量	23 M☉
半徑	3.25 R☉
亮度 (bolometric)	620,000 L☉
溫度	89,100 K
companion
質量	1.5 M☉
其他命名
	EZ CMa、ALS]] 98、CD−23°4553、CEL（英语：List of astronomical catalogues#C） 1426、科林德 121 4、CPD−23°1588、GC 9061、HD 50896、Hen（英语：Karl Gordon Henize#Writings） 3-20、HIP 33165、HR 2583、LBN 1052、MR 6、PPM 251223、SAO 172546、SH 2-308、TYC 6522-3270-1、WR 6
參考資料庫
SIMBAD	资料

大犬座EZ（縮寫為EZ CMa，也被稱為WR 6）是在星座大犬座的一對聯星。主星是沃夫–瑞葉星，並且最亮的10顆沃夫–瑞葉星之一，視星等比7等更亮^[8]。

聯星系統

大犬座EZ的視星等在3.766天的時間內在6.71到6.95之間變化，同時光譜也發生了變化^[9]。有人提出，它可能是以中子星為伴星的聯星，以該週期完成繞沃夫–瑞葉星的軌道，這就是造成這些變化的原因。《變星總表》在此基礎上將其列為可能的激變變星。有人認為伴星不存在，光譜變化是由恆星表面的活動引起的^[9]。

從2015年底到2016年初的四個月時間裏，對光照變化的觀測證實了明顯的7000376000000000000♠3.76 天變化。這被解釋為一個7005316224000000000♠3.66 d軌道週期，快速拱點進動（英语：Apsidal precession）在大約100天內完成完整的旋轉。軌道傾斜在60-74度左右，每個軌道週期上有兩次星食^[7]。

沃夫–瑞葉星和星雲

WN4的光譜類型表明它是一顆非常熱的恆星，這導致了非常高的光度，主要以紫外線輻射的形式發射。光譜顯示一顆恆星表面完全沒有氫^[4]。

大犬座EZ被一個微弱的氣泡星雲包圍：被高達1,700公里/秒的恆星風吹起，並被強烈的紫外線輻射電離的一個小H_II region。這個氣泡星雲被編目為Sharpless Sh2-308，或者只是S308^[6]。它很可能是非常分散的疏散星團 Collinder121，在橙色超巨星周圍發現ο¹ CMa。

參考資料

^ ^1.0 ^1.1 Van Leeuwen, F. Validation of the new Hipparcos reduction. Astronomy and Astrophysics. 2007, 474 (2): 653–664. Bibcode:2007A&A...474..653V. S2CID 18759600. arXiv:0708.1752 . doi:10.1051/0004-6361:20078357.
^ ^2.0 ^2.1 ^2.2 Ducati, J. R. VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system. CDS/ADC Collection of Electronic Catalogues. 2002, 2237: 0. Bibcode:2002yCat.2237....0D.
^ ^3.0 ^3.1 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.
^ ^4.0 ^4.1 ^4.2 ^4.3 ^4.4 ^4.5 ^4.6 Sota, A.; Maíz Apellániz, J.; Morrell, N. I.; Barbá, R. H.; Walborn, N. R.; Gamen, R. C.; Arias, J. I.; Alfaro, E. J.; Oskinova, L. M. The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters. Astronomy & Astrophysics. 2019, A57: 625. Bibcode:2019A&A...625A..57H. S2CID 104292503. arXiv:1904.04687 . doi:10.1051/0004-6361/201834850.
^ ^5.0 ^5.1 ^5.2 Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; et al. Gaia Data Release 2. Summary of the contents and survey properties. Astronomy & Astrophysics. 2018. Bibcode:2018A&A...616A...1G. arXiv:1804.09365 . doi:10.1051/0004-6361/201833051. VizieR中此天体在盖亚望远镜第二批数据发布的记录
^ ^6.0 ^6.1 Toalá, J. A.; Guerrero, M. A.; Ramos-Larios, G.; Guzmán, V. WISE morphological study of Wolf-Rayet nebulae. Astronomy & Astrophysics. 2015, 578: A66. Bibcode:2015A&A...578A..66T. ISSN 0004-6361. S2CID 55776698. arXiv:1503.06878 . doi:10.1051/0004-6361/201525706.
^ ^7.0 ^7.1 ^7.2 Schmutz, W.; Koenigsberger, G. Long uninterrupted photometric observations of the Wolf-Rayet star EZ CMa by the Toronto BRITE satellite reveal a very fast apsidal motion. Astronomy & Astrophysics. 2019, 624: L3. Bibcode:2019A&A...624L...3S. S2CID 85459362. arXiv:1903.09501 . doi:10.1051/0004-6361/201935094.
^ Van Der Hucht, Karel A. The VIIth catalogue of galactic Wolf–Rayet stars. New Astronomy Reviews. 2001, 45 (3): 135–232. Bibcode:2001NewAR..45..135V. doi:10.1016/S1387-6473(00)00112-3.
^ ^9.0 ^9.1 St-Louis, Nicole; Dalton, M. J.; Marchenko, S. V.; Moffat, A. F. J.; Willis, A. J. The [ITAL]IUE[/ITAL] Mega Campaign: Wind Structure and Variability of HD 50896 (WN5). The Astrophysical Journal. 1995, 452. Bibcode:1995ApJ...452L..57S. S2CID 117990494. doi:10.1086/309706.
^ MAST: Barbara A. Mikulski Archive for Space Telescopes. Space Telescope Science Institute. [8 December 2021]. （原始内容存档于2023-03-27）.

外部連結

[hipparcos-1] 1.0 ^1.1 Van Leeuwen, F. Validation of the new Hipparcos reduction. Astronomy and Astrophysics. 2007, 474 (2): 653–664. Bibcode:2007A&A...474..653V. S2CID 18759600. arXiv:0708.1752 . doi:10.1051/0004-6361:20078357.

[ducati-2] 2.0 ^2.1 ^2.2 Ducati, J. R. VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system. CDS/ADC Collection of Electronic Catalogues. 2002, 2237: 0. Bibcode:2002yCat.2237....0D.

[gcvs-3] 3.0 ^3.1 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.

[wn-4] 4.0 ^4.1 ^4.2 ^4.3 ^4.4 ^4.5 ^4.6 Sota, A.; Maíz Apellániz, J.; Morrell, N. I.; Barbá, R. H.; Walborn, N. R.; Gamen, R. C.; Arias, J. I.; Alfaro, E. J.; Oskinova, L. M. The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters. Astronomy & Astrophysics. 2019, A57: 625. Bibcode:2019A&A...625A..57H. S2CID 104292503. arXiv:1904.04687 . doi:10.1051/0004-6361/201834850.

[dr2-5] 5.0 ^5.1 ^5.2 Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; et al. Gaia Data Release 2. Summary of the contents and survey properties. Astronomy & Astrophysics. 2018. Bibcode:2018A&A...616A...1G. arXiv:1804.09365 . doi:10.1051/0004-6361/201833051. VizieR中此天体在盖亚望远镜第二批数据发布的记录

[ToaláGuerrero2015-6] 6.0 ^6.1 Toalá, J. A.; Guerrero, M. A.; Ramos-Larios, G.; Guzmán, V. WISE morphological study of Wolf-Rayet nebulae. Astronomy & Astrophysics. 2015, 578: A66. Bibcode:2015A&A...578A..66T. ISSN 0004-6361. S2CID 55776698. arXiv:1503.06878 . doi:10.1051/0004-6361/201525706.

[schmutz-7] 7.0 ^7.1 ^7.2 Schmutz, W.; Koenigsberger, G. Long uninterrupted photometric observations of the Wolf-Rayet star EZ CMa by the Toronto BRITE satellite reveal a very fast apsidal motion. Astronomy & Astrophysics. 2019, 624: L3. Bibcode:2019A&A...624L...3S. S2CID 85459362. arXiv:1903.09501 . doi:10.1051/0004-6361/201935094.

[hucht-8] Van Der Hucht, Karel A. The VIIth catalogue of galactic Wolf–Rayet stars. New Astronomy Reviews. 2001, 45 (3): 135–232. Bibcode:2001NewAR..45..135V. doi:10.1016/S1387-6473(00)00112-3.

[StLouis1995-9] 9.0 ^9.1 St-Louis, Nicole; Dalton, M. J.; Marchenko, S. V.; Moffat, A. F. J.; Willis, A. J. The [ITAL]IUE[/ITAL] Mega Campaign: Wind Structure and Variability of HD 50896 (WN5). The Astrophysical Journal. 1995, 452. Bibcode:1995ApJ...452L..57S. S2CID 117990494. doi:10.1086/309706.

[MAST-10] MAST: Barbara A. Mikulski Archive for Space Telescopes. Space Telescope Science Institute. [8 December 2021]. （原始内容存档于2023-03-27）.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]