Magnetic Flares on Asymptotic Giant Branch Stars
نویسندگان
چکیده
We investigate the consequences of magnetic flares on the surface of asymptotic giant branch (AGB) and similar stars. In contrast to the solar wind, in the winds of AGB stars the gas cooling time is much shorter than the outflow time. As a result, we predict that energetic flaring should enhance, rather than inhibit, dust formation around AGB stars. Analysis of an archival ROSAT X-ray spectrum of the Mira system yields results for intrinsic X-ray luminosity (∼ 2× 10 erg s) and temperature (∼ 10 K) that are consistent with coronal emission from the AGB star Mira A, although it also possible that the X-ray emission arises from accretion onto its hot companion, Mira B. Subject headings: stars: mass loss — stars: winds, outflows — X-rays: ISM — stars: AGB — stars: magnetic fields
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