Related papers: Evolution and pulsation period change in the Large…

Non-local, time-dependent convection models have been used to explain the location of double-mode pulsations in Cepheids in the HR diagram as well as the existence and location of the red edge of the instability strip. These properties are…

Pulsation period evolution during the helium-shell flash in the Mira variable R Hya is investigated using consistent stellar evolution and non-linear stellar pulsation computations. The initial and time-dependent inner boundary conditions…

The 6.7 GHz methanol maser emission, a tracer of forming massive stars, sometimes shows enigmatic periodic flux variations over several 10-100 days. In this Letter, we propose that this periodic variations could be explained by the…

This work presents the study of multiphase relations of classical Cepheids in the Magellanic Clouds for short periods (log P < 1) and long periods (log P > 1). From the analysis, it has been found that the multiphase relations obtained…

We present the results of a study of the type II Cepheid ($P_{puls} = 4.974 d$) in the eclipsing binary system OGLE-LMC-T2CEP-098 ($P_{orb} = 397.2 d$). The Cepheid belongs to the peculiar W Vir group, for which the evolutionary status is…

Previous nonlinear fundamental pulsation models for classical Cepheids with metal content Z <= 0.02 are implemented with new computations at super-solar metallicity (Z=0.03, 0.04) and selected choices of the helium-to-metal enrichment ratio…

The Cepheid variables in SMC, LMC, the Milky Way, M33 and M31 are used to examine the dependence of pulsation mode on metallicity which was previously found in red supergiants. The initial samples of Cepheids are collected from the Cepheid…

We present the results of a nonadiabatic, linear stability analysis of models of very low-mass stars (VLMSs) and brown dwarfs (BDs) during the deuterium burning phase in the center. We find unstable fundamental modes with periods varying…

During stellar evolution, especially in the PMS, stellar structure and rotation evolve significantly causing major changes in the dynamics and global flows of the star. We wish to assess the consequences of these changes on stellar dynamo,…

Aims: We attempt to revise the period-amplitude (P-A) relationship of Galactic Cepheids based on multi-colour photometric and radial velocity data. Reliable P-A graphs for Galactic Cepheids constructed for the U, B, V, R_C, and I_C…

The OGLE project led to discovery of earlier unknown forms of multiperiodic pulsation in Cepheids. Often, the observed periods may be explained in terms of simultaneous excitation of two or rarely three radial modes. However, a secondary…

Updated evolutionary and pulsational model predictions are combined in order to interpret the properties of Galactic Classical Cepheids in the Gaia Data Release 2. In particular, the location of the instability strip boundaries and the…

An analytical derivation is presented for computing mass-loss rates of Cepheids by using the method of Castor, Abbott, & Klein (1975) modified to include a term for momentum input from pulsation and shocks generated in the atmosphere. Using…

We present an analysis of the theoretical and observed light curve parameters of the fundamental mode (FU) classical Cepheids in the Magellanic Clouds in $V$- and $I$- photometric bands. The state-of-the-art 1D non-linear radial stellar…

Stellar evolution calculations to the stage of the cooling white dwarf were done for population~I stars with masses on the main sequence $1M_\odot\le M_0\le 1.5M_\odot$. The final helium flash LTP is shown to occur in post--AGB stars with…

We performed a new and accurate fit of light and radial velocity curves of the Large Magellanic Cloud (LMC) Cepheid --OGLE-LMC-CEP-0227-- belonging to a detached double-lined eclipsing binary system. We computed several sets of nonlinear,…

The structure and evolution of the disk of the Small Magellanic Cloud (SMC) are traced by studying the Cepheids. We aim to estimate the orientation measurements of the disk, such as the inclination and the position angle of the line of…

Pulsating stars are universally recognized as precise distance indicators and tracers of stellar populations. Their variability, combined with well-defined relationships between pulsation properties and intrinsic evolutionary parameters…

We review ways in which observations of the changing periods of pulsating variable stars can be used to detect and directly measure their evolution. We briefly describe the two main techniques of analysis -- (O-C) analysis and wavelet…

We present a dense model grid with tailored input chemical composition appropriate for the Large Magellanic Cloud. We use a one-dimensional hydrodynamic stellar evolution code, which accounts for rotation, transport of angular momentum by…