Continuum IR emission of Be star wind-compressed discs
نویسنده
چکیده
A prescription for the density of a wind compressed disc (WCD) is given and the IRemissionof the disc is calculated. The prescription enables emission fromWCDs to be calculated simply without recourse to full 2 1 2 -dimensional (2 1 2 -D) modelling of rotating radiatively driven winds. It is shown that the standard WCD model is incapable of representing observed Be star discs. As a guide for future research, various addenda to theWCD model are considered: internal density structure of the disc, decoupling of thematter and radiation fields in thewind and finally magnetic fields. Of these, it is only a magnetic field which may be sufficient as a suffix to bring the WCD model into line with observations. The magnetic field strength must be tens of gauss to begin to reproduce observations.
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