Radio and infrared structure of the colliding-wind Wolf-Rayet system WR 147

被引:115
作者
Williams, PM
Dougherty, SM
Davis, RJ
vanderHucht, KA
Bode, MF
Gunawan, DYAS
机构
[1] UNIV CALGARY,CALGARY,AB T2N 1N4,CANADA
[2] DOMINION RADIO ASTROPHYS OBSERV,PENTICTON,BC V2A 6K3,CANADA
[3] UNIV MANCHESTER,NUFFIELD RADIO ASTRON LABS,JODRELL BANK,MACCLESFIELD SK11 9DL,CHESHIRE,ENGLAND
[4] SRON,NL-3584 CA UTRECHT,NETHERLANDS
[5] LIVERPOOL JOHN MOORES UNIV,SCH ELECT ENGN ELECT & PHYS,ASTRON GRP,LIVERPOOL L3 3AF,MERSEYSIDE,ENGLAND
关键词
stars; individual; WR; 147; Wolf-Rayet; radio continuum; X-rays;
D O I
10.1093/mnras/289.1.10
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
New, high-resolution infrared and radio images of the X-ray-luminous Wolf-Rayet system WR 147 (AS 431) are presented. The 5-GHz radio image resolves both components of this double source. The emission from one component, that to the south and associated with the wind of the WN8 star, has an extent of similar to 170 x 253 mas(2), indicating that the stellar wind is not spherically symmetric. The second, non-thermal component similar to 0.6 arcsec north of the WN8 star is extended east-west to similar to 267 mas. The infrared image reveals the presence of a companion to the WN8 star, close to the non-thermal radio source but slightly (similar to 60 mas) more distant from the WN8 star. The companion is Delta K similar to 3 mag fainter than the WN8 star and has a luminosity of a B0.5V star, just sufficiently luminous to possess a stellar wind capable of colliding with that of the WN8 star. The presence of the non-thermal emission between the two stars and much closer to that with the weaker wind is direct evidence for a colliding-wind origin for the emission, A significant portion of the X-ray emission can also be accounted for by the release of energy in the wind collision. Comparison of the non-thermal Bur with those of the three systems incorporating WC-type stars (WR 125, WR 140 and WR 146) shows a correlation with velocity of the WR wind.
引用
收藏
页码:10 / 20
页数:11
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