Research Note

The role of the stellar rotation on the internal constitution of PV Cassiopeiae

Instituto de Astrofísica de Andalucía, CSIC, Apartado 3004, 18080 Granada, Spain e-mail: claret@iaa.es

Received: 6 November 2007
Accepted: 23 August 2008

Abstract

Aims. It has been suggested that the observed apsidal-motion of PV Cas agrees with theoretical predictions. However, this view is not supported by other investigations of the same system. By using standard and rotating models, we re-analyse the evolutionary status of PV Cas, which is poorly established, especially its apsidal-motion.

Methods. We computed standard (without rotation) stellar models for the precise observed masses of PV Cas by considering a moderate amount of core overshooting (). Rotating models – assuming solid-body rotation and local conservation of angular momentum – were also computed to verify the influence of rotation on the astrophysical properties of the system.

Results. Considering the limitations of the theoretical models, rotation does not appear to have a significant influence on the modelling of PV Cas. Rotating, in addition to standard models, are able to reproduce the the masses, radii, and TR (effective temperature ratio) of PV Cas without a rapidly rotating core, surrounded by a slowly rotating envelope. Although our rotating models provide more mass-concentrated configurations, the improvement is insufficient to reproduce the observed apsidal-motion rate. Given the error bars, the discrepancy between theory and observation, in terms of apsidal-motion, appears to be real.