The peculiar single giant HD 112989 : rotation , activity and evolution ?
نویسنده
چکیده
A spectroscopic, photometric and evolutionary study is presented for HD 112989, an active peculiar giant star. The present spectroscopic observations show a significant CaII K&H emission core variability, whereas the UBV photometry shows that HD 112989 has a variable brightness. The rotational velocity for this star, 11.0 kms−1, is about five times larger than the mean rotational velocity for giants with the same spectral type. In addition, we have found no sign of binarity for this star.
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