Asteroseismology of the GW Virginis stars SDSS J0349-0059 and VV 47

TL;DR

This paper uses advanced asteroseismology techniques to determine the masses and rotation periods of GW Virginis stars SDSS J0349-0059 and VV 47, demonstrating high precision in stellar characterization.

Contribution

It provides the first detailed asteroseismological analysis of these stars using complete evolutionary PG 1159 models, improving mass and rotation period estimates.

Findings

Mass of SDSS J0349-0059 is approximately 0.542 solar masses.

Mass of VV 47 is approximately 0.528 solar masses.

Rotation period of SDSS J0349-0059 is about 0.407 days.

Abstract

We present an asteroseismological study of SDSS J0349-0059 and VV 47 aimed mainly at deriving their total mass on the basis of state-of-the-art PG 1159 evolutionary models. We compute adiabatic nonradial $g$-mode pulsation periods for PG 1159 evolutionary models with stellar masses ranging from $0.515$ to $0.741\ M_{\sun}$, that take into account the complete evolution of the progenitor stars. We first estimate a mean period spacing for both SDSS J0349-0059 and VV 47. By comparing the observed period spacing with the asymptotic period spacing we obtain $M_{\star}\sim 0.569\ M_{\sun}$ for SDSS J0349-0059 and $M_{\star}\sim 0.523\ M_{\sun}$ for VV 47. If we compare the observed period spacing with the average of the computed period spacings we found $M_{\star}\sim 0.535\ M_{\sun}$ for SDSS J0349-0059 and $M_{\star}\sim 0.528 M_{\sun}$ for VV 47. Searching for the best period fit we found, in the case of SDSS J0349-0059, an asteroseismological model with $M_{\star}= 0.542\ M_{\sun}$ and $T_{\rm eff}= 91\, 255\ $K. For VV 47, we could not find a unique and unambiguous asteroseismological model. Finally, for SDSS J0349-0059, we determined the rotation period as being $P_{\rm rot}= 1/\Omega \sim 0.407$ days. The results presented in this work constitute a further step in the study of GW Vir stars through asteroseismology in the frame of fully evolutionary models of PG 1159 stars. In particular, once again it is shown the potential of asteroseismology to derive stellar masses of PG 1159 stars with an unprecedented precision.