Spectroscopy of the variable K-dwarf UNSW-V-760: is it a pre-main-sequence pulsator?
Date
2013Author
Koen, Chris
Gray, Richard O.
Kawaler, S.
Crawford, S. M.
Metadata
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The star UNSW-V-760 is a known variable, showing both flares and two non-sinusoidal
periodicities. Availability of high signal-to-noise spectra reported in this paper has enabled
a revision of the spectral type of this star to K3 IV-Vk. The star is a very rapid rotator
(v sin i ∼ 140 km s−1), and the abundance of lithium appears to be enhanced. 48 radial velocity
measurements were obtained over the course of three successive nights. These may show the
same two frequencies detected photometrically, but there is some uncertainty in the interpretation.
Application of pulsation theory suggests that photometric frequencies could be explained
as low pulsation modes, but an excitation mechanism remains to be found.