IALP 13078
INSTITUTO DE ASTROFISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Formation and evolution of helium white dwarfs in the old metal-rich open cluster NGC 6791
Autor/es:
A. ROMERO, J. PANEI Y L. ALTHAUS
Lugar:
La Plata, Argentina
Reunión:
Otro; First La Plata International School on Astronomy and Geophysics; 2008
Institución organizadora:
Fac. de Cs. Astronómicas y Geofísicas, UNLP
Resumen:
NGC 6791 is both the oldest (8 Gyr) and most metal-rich ([Fe/H]= +0.4) open cluster in our Galaxy. This cluster containsa large blue straggler population, and an extremely blue horizontalbranch. In addition, it has been shown that two-thirds of the NGC6791 members white dwarfs have masses below 0.46 solar masses atwhich helium is ignited in the core. In particular extreme horizontalbranch stars, and also low mass helium white dwarf, can be formed as aresult of increased mass loss in post main sequence evolutionarystages, since mass loss is much more efficient in high metallicityenvironments.In this work we explore the formation and evolution of low mass heliumwhite dwarfs in a high metallicity environment. We compute fullevolutionary sequences from the beginning of the main sequence to thewhite dwarf cooling curve, considering the single stellar evolutionarychannel with strong mass loss on the red giant branch.
