The Core - Wing Anomaly of Cool Ap Stars ? Abnormal Balmer Pro

نویسنده

  • Charles R. Cowley
چکیده

The prooles of H in a number of cool Ap stars are anomalous. Broad wings, indicative of temperatures in the range 7000-8000K end abruptly in narrow cores. The widths of these cores are compatible with those of dwarfs with temperatures of 6000K or lower. This pro-le has been known for Przybylski's star, but it is seen in other cool Ap's. The H proole in several of these stars shows a similar core-wing anomaly (CWA). In Przybylski's star, the CWA is probably present at higher Balmer members. We are unable to account for these prooles within the context of LTE and normal dwarf atmospheres. We conclude that the atmospheres of these stars are not \nor-mal." This is contrary to a notion that has long been held.

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تاریخ انتشار 2007