IALP   13078
INSTITUTO DE ASTROFISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Period and amplitude changes in the GW Vir variable star PG 0122+200: evidence for resonant coupling
Autor/es:
G. VAUCLAIR; J. -N. FU; J. -E. SOLHEIM; S. -L. KIM; N. DOLEZ; M. CHEVRETON; L. CHEN; M. A. WOOD; I. M. SILVER; Z. BOGNAR; M. PAPARÓ; A. H. CÓRSICO
Lugar:
Hakone
Reunión:
Seminario; The 61st Fujihara seminar: Progress in solar/stellar physics with helio- and asteroseismology; 2011
Institución organizadora:
Fujihara Foundation of Science
Resumen:
G 0122+200 is the coolest GW Vir pulsator (Teff= 80kK). At this phase of the pre-white dwarf stars evolution, theoretical models predict that neutrinos should contribute substantially to the cooling. It was anticipated that measuring the rate of change of the pulsation periods could directly determine the evolutionary time scale and so constrain the neutrino emission rate. This was the motivation for the follow up observations of the star. We summarize here the results on the frequency and amplitude changes observed on a 22 years period  (1986 to 2008). We find that those variations show too short time scales and large amplitudes to be due to the cooling. Another mechanism must be invoked. We suggest that the resonant coupling induced by rotation could be the relevant mechanism.