Stellar rotation periods determined from simultaneously measured Ca II H&K and Ca II IRT lines
نویسندگان
چکیده
منابع مشابه
Rotation velocities of white dwarfs determined from the Ca II K line
We determine projected rotation velocities v sin i in DAZ white dwarfs, for the first time using the rotational broadening of the Ca II K line. The results confirm previous findings that white dwarfs are very slow rotators, and set even more stringent upper limits of typically less than 10 km s−1. The few exceptions include 3 stars known or suspected to be variable ZZ Ceti stars, where the line...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2017
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201630262