Pa - beta as a chromospheric diagnostic in M dwarfs
نویسندگان
چکیده
We have obtained, for the first time, a high resolution near-infrared spectrum in the region of Paβ of a chromospheri-cally active M dwarf (AU Mic). We demonstrate that both Paβ and Hα can be fit with a model of large chromospheric pressure , but that the two lines indicate clearly different values of the exact pressure. There are several important types of missing physics that need to be included in the calculations before the importance of this apparent discrepancy can be assessed. Nevertheless, the approximate agreement of the two lines lends support to an earlier theoretical result that the Paschen series is a useful chromospheric diagnostic in M dwarfs.
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تاریخ انتشار 1997