2009MNRAS.399.1954B

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 0.680M_☉. The three `favoured' models have M_H between 2.5x10^–5 and 6.3x10^–6M_*and give 14.2-14.8mas seismological parallax. The 0.645M_☉(11400K) model also matches the spectroscopic logg and T_eff within 1σ. We investigated the possibility of mode trapping and concluded that while it can explain high amplitude modes, it is not required.