2018/09/24 by Calcaferro, L. M., Córsico, A. H., Althaus, L. G. +2
#FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR)
paper · doi:10.48550/arxiv.1809.09242
Many low-mass white dwarfs are being discovered in the field of our galaxy and some of them exhibit g-mode pulsations, comprising the extremely low-mass variable (ELMV) stars class. Despite it is generally believed that these stars are characterized by thick H envelopes, from stellar evolution considerations, the existence of low-mass WDs with thin H envelopes is also possible. We have performed detailed asteroseismological fits to all the known ELMVs to search for a representative model by employing a set of fully evolutionary models that are representative of low-mass He-core white dwarf stars with a range of stellar masses [0.1554-0.4352] M\odot, effective temperatures [6000-10000] K, and also with a range of H envelope thicknesses -5.8 \lesssim log(M\rm H/M⋆) \lesssim -1.7, hence expanding the space of parameters. We found that some of the stars under analysis are characterized by thick H envelopes, but others are better represented by models with thin H envelope.