TY - GEN

T1 - Superfast spectral variations of OBA stars

AU - Batrakov, A. A.

AU - Kholtygin, A. F.

AU - Hubrig, S.

AU - Fabrika, S.

AU - Valeev, A. F.

AU - Kostenkov, A. E.

PY - 2020

Y1 - 2020

N2 - Results of our recent search for superfast line-profile variations (LPVs) in spectra of the bright OBA stars HD 93521 (O9.5III), $\rho$ Leo (B1Iab), $\alpha^2$ CVn, and $\gamma$\,UMi are presented. The spectra were obtained using the multi-mode focal reducer SCORPIO on the Russian 6-m telescope. Both regular LPVs with periods from 2 to 90 minutes and non-regular LPVs on time-scales of seconds were detected. Such short-term spectral variability in massive OBA stars has not been studied systematically before. These studies can be crucial for understanding the physics of type-II supernova and for improved modelling of stellar evolution.

AB - Results of our recent search for superfast line-profile variations (LPVs) in spectra of the bright OBA stars HD 93521 (O9.5III), $\rho$ Leo (B1Iab), $\alpha^2$ CVn, and $\gamma$\,UMi are presented. The spectra were obtained using the multi-mode focal reducer SCORPIO on the Russian 6-m telescope. Both regular LPVs with periods from 2 to 90 minutes and non-regular LPVs on time-scales of seconds were detected. Such short-term spectral variability in massive OBA stars has not been studied systematically before. These studies can be crucial for understanding the physics of type-II supernova and for improved modelling of stellar evolution.

KW - Stars: early-type

KW - variables: general

KW - line profiles

M3 - Conference contribution

SP - 163

EP - 164

BT - Proceedings of the conference Stars and their Variability Observed from Space, held in Vienna on August 19-23, 2019.

T2 - Stars and their variability observed from Space

Y2 - 19 August 2020 through 23 December 2020

ER -