Work

Long-Term Stability of Chemical Spots and Reasons for the Period Variations in Ap Star CU Vir

Year: 2025

Type: article

Abstract: We present the results of Doppler Imaging of the Ap star CU Vir in the silicon lines over the 1985–2011 time span, as well as multi-element imaging in the 2009/2011 epoch. The surface distribution of silicon in CU Vir exhibits stability over the approximately 26 years studied: the number, shape, and mutual distribution of the overabundance spots have remained unchanged. The modelling of the light curve based on the surface elemental distribution obtained with DI did not reveal any significant changes in the shape of the light curve that could explain the photometric phase shift observed in CU Vir. Consequently, the phase shifts and changes in the photometric period of CU Vir are caused by the rigid longitudinal drift of the surface-abundance structures. We performed simulations of the Tayler instability of the background magnetic field of CU Vir, and discuss the possibility of explaining the period variations by the drift of surface instability modes.

Source: Galaxies

DOI: 10.3390/galaxies13040090

Authors: Ilya Potravnov, Tatiana Ryabchikova, Leonid Kitchatinov, Yuri Pakhomov

Institutions: Russian Academy of Sciences, Institute of Astronomy, Institute of Solar-Terrestrial Physics, Siberian Branch of the Russian Academy of Sciences

Language: English

Topic: Stellar, planetary, and galactic studies

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,689

OpenAlex ID: W4413175752

FWCI: 0.457

Cites: 70

Cited by: 1

Related to: 10