Valentina Klochkova, Vladimir Panchuk
High-resolution echelle spectra taken with the 6-m telescope in 2003-2011 are
used to study features of the optical spectrum and the velocity field in the
atmosphere of the semiregular variable LN Hya in detail. The weak symmetric
photospheric absorptions indicate radial velocity variations from night to
night (by as much as 3 km/s), resulting from small pulsations. Peculiarities
and profile variations were found for strong lines of FeI, FeII, BaII, SiII,
etc. The profiles of these lines were asymmetric: their short-wave wings were
extended and their cores were either split or distorted by emission. During the
2010 observing season, the position and depth of the Halpha absorption
component, the intensities of the short and long-wave emission components, and
the intensity ratio of the latter components varied from spectrum to spectrum.
Weak emissions of neutral atoms (VI, MnI, CoI, NiI, FeI) appeared in the
spectrum of June 1, 2010. All these spectral peculiarities, recorded for the
first time, suggest that we have detected rapid changes in the physical
conditions in the upper atmospheric layers of LN Hya in 2010.
View original:
http://arxiv.org/abs/1112.3732
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