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Probing Colliding Wind Binaries with High-Resolution X-ray Spectra

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 نشر من قبل David B. Henley
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English
 تأليف D.B. Henley




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X-ray line profiles represent a new way of studying the winds of massive stars. In particular, they enable us to probe in detail the wind-wind collision in colliding wind binaries, providing new insights into the structure and dynamics of the X-ray-emitting regions. We present the key results of new analyses of high-resolution Chandra X-ray spectra of two important colliding wind systems, Gamma Velorum and WR140. The lines of Gamma Vel are essentially unshifted from their rest wavelengths, which we suggest is evidence of a wide shock opening angle, indicative of sudden radiative braking. The widths of the lines of WR140 are correlated with ionization potential, implying non-equilibrium ionization. The implications of these results for the radio emission from these systems are discussed, as are some of the future directions for X-ray line profile modelling of colliding wind binaries.



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