Non - gaussian statistics and stellar rotational velocities of main sequence field stars
نویسنده
چکیده
In this letter we study the observed distributions of rotational velocity in a sample of more than 16,000 nearby F and G dwarf stars, magnitude complete and presenting high precision V sini measurements. We show that the velocity distributions cannot be fitted by a maxwellian. On the other hand, an analysis based on both Tsallis and Kaniadakis power-law statistics is by far the most appropriate statistics and give a very good fit. It is also shown that single and binary stars have similar rotational distributions. This is the first time, to our knowledge, that these two new statistics are tested for the rotation of such a large sample of stars, pointing solidly to a solution of the puzzling problem on the function governing the distribution of stellar rotational velocity Subject headings: stars: rotation–statistics–evolution–fundamental parameters
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تاریخ انتشار 2009