New results in RR Lyrae modeling: convective cycles, additional modes and more

TL;DR

This paper reviews recent advances in RR Lyrae star modeling and observations, highlighting new findings on pulsation modes, convective cycles, and the potential explanations for the Blazhko effect.

Contribution

It presents new observational and theoretical results, including the detection of additional pulsation modes and the evaluation of models explaining the Blazhko effect.

Findings

Detection of additional modes in RR Lyrae stars

Convective cycle model is unlikely for short- and medium-period modulations

Radial resonance model shows increasing plausibility

Abstract

Recent theoretical and observational findings breathed new life into the field of RR Lyrae stars. The ever more precise and complete measurements of the space asteroseismology missions revealed new details, such as the period doubling and the presence of the additional modes in the stars. Theoretical work also flourished: period doubling was explained and an additional mode has been detected in hydrodynamic models as well. Although the most intriguing mystery, the Blazhko-effect has remained unsolved, new findings indicate that the convective cycle model can be effectively ruled out for short- and medium-period modulations. On the other hand, the plausibility of the radial resonance model is increasing, as more and more resonances are detected both in models and stars.