No fundamental-mode pulsation in R Leonis?

THE EVOLVING SHAPES OF o CETI AND R LEONIS

The sizes and shapes of the stars o Ceti and R Leonis have been measured in the mid-infrared. The observations were made using the UC Berkeley Infrared Spatial Interferometer (ISI), and they reveal details about the size, shape and asymmetry of both stars over several epochs in 2006. The star o Ceti appears to be rather symmetric, while the shape of R Leonis appears more consistent with a unifo...

Interferometric observations of R Leonis in the K band First direct detection of the photospheric pulsation and study of the atmospheric intensity distribution

The Mira-type star R Leonis was observed at two different epochs in the K band with the FLUOR beam combiner on the IOTA interferometer. A variation of diameter is clearly detected for the very first time at this wavelength revealing an apparent pulsation of atmospheric layers very close to the stellar photosphere. We discuss the excess of visibility measured at high spatial frequencies and show...

A&a Manuscript No. Pulsation Models of Scuti Variables I. the High{amplitude Double{mode Stars

The relations between high{amplitude Scuti stars and the much more abundant low{amplitude Sct variables are not clear. Both groups have similar periods and seem to have almost the same basic physical properties , although their light{curve characteristics are very diierent. In the last few years much improved observational data have been published, and improved theoretical physics | in particul...

Double Mode Pulsation as a Resonance Phenomenon

Probable nonradial g - mode pulsation in early A - type stars ⋆

A survey for line profile variability in early A-type stars has been performed in order to detect nonradial pulsation signatures. The star HR 6139, with spectral type A2V and estimated T eff = 8800 K, shows evident line profile variations that can be explained by oscillations in prograde g-modes. This feature and the known photometric variability are similar to those observed in the Slowly Puls...