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arXiv · 2202.00971

Determining rotational and macroturbulent velocities of cool magnetic giant stars

Stefan Georgiev·Agnès Lèbre·Eric Josselin·Renada Konstantinova-Antova·Julien Morin
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Abstract

An original method of estimating the projected rotational velocity, $vsini$, and the macroturbulent velocity, $v_{\rm mac}$, of evolved M giant stars is presented. It is based on the use of spectrum synthesis and multi-line analysis tools. The goal is to fit the mean line profile of observations with that of synthetic spectra. The method is applied to the red giant star RZ Ari and the results $v\sin i$ = 6.0 $\pm$ 0.5 km/s and $v_{\rm mac}$ = 2.0 $\pm$ 1.0 km/s are obtained.

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Stefan Georgiev, Agnès Lèbre, Eric Josselin, Renada Konstantinova-Antova, Julien Morin. 2022-02-02. Determining rotational and macroturbulent velocities of cool magnetic giant stars. https://doi.org/10.1002/asna.202013725

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