L. M. Oskinova, W. -R. Hamann, J. P. Cassinelli, J. C. Brown, H. Todt
We investigate the connections between the magnetic fields and the X-ray
emission from massive stars. Our study shows that the X-ray properties of known
strongly magnetic stars are diverse: while some comply to the predictions of
the magnetically confined wind model, others do not. We conclude that strong,
hard, and variable X-ray emission may be a sufficient attribute of magnetic
massive stars, but it is not a necessary one. We address the general properties
of X-ray emission from "normal" massive stars, especially the long standing
mystery about the correlations between the parameters of X-ray emission and
fundamental stellar properties. The recent development in stellar structure
modeling shows that small scale surface magnetic fields may be common. We
suggest a "hybrid" scenario which could explain the X-ray emission from massive
stars by a combination of magnetic mechanisms on the surface and shocks in the
stellar wind. The magnetic mechanisms and the wind shocks are triggered by
convective motions in sub-photospheric layers. This scenario opens the door for
a natural explanation of the well established correlation between bolometric
and X-ray luminosities.
View original:
http://arxiv.org/abs/1110.5345
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