We present the results on period search and modelling of the cool DAV star KUV 02464+3239. Our observations resolved the multiperiodic pulsational behaviour of the star. In agreement with its position near the red edge of the DAV instability strip, it shows large amplitude, long-period pulsation modes, and has a strongly non-sinusoidal light curve. We determined six frequencies as normal modes and revealed remarkable short-term amplitude variations. A rigorous test was performed for the possible source of amplitude variation: beating of modes, effect of noise, unresolved frequencies or rotational triplets. Among the best-fitting models resulting from a grid search, we selected three that gave l = 1 solutions for the largest amplitude modes. These models had masses of 0.645, 0.650 and 0.680 M⊙. The three 'favoured' models have MH between 2.5 × 10-5 and 6.3 × 10 -6 M* and give 14.2-14.8 mas seismological parallax. The 0.645 M⊙ (11 400 K) model also matches the spectroscopic log g and Teff within 1σ. We investigated the possibility of mode trapping and concluded that while it can explain high amplitude modes, it is not required.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science