相关论文: The shapes of light curves of Mira-type variables
About 10% of upper main sequence stars are characterised by the presence of chemical peculiarities, often found together with a structured magnetic field. The atmospheres of most of those chemically peculiar stars present surface spots,…
Stars are not perfectly spherically symmetric. They are deformed by rotation and magnetic fields. Until now, the study of stellar shapes has only been possible with optical interferometry for a few of the fastest-rotating nearby stars. We…
The studies of pulsating variable stars are traditional subjects of astronomers in Odessa. In the last half of the 20th century, the studies of the physical variable stars were the topics of 15 PhD theses of the collaborators of the Odessa…
Mira and semi-regular variable stars have been studied for centuries but continue to be enigmatic. One unsolved mystery is the presence of polarization from these stars. In particular, we present 40 years of polarization measurements for…
The properties of the Milky Way's nuclear stellar disc give crucial information on the epoch of bar formation. Mira variables are promising bright candidates to study the nuclear stellar disc, and through their period-age relation dissect…
Many astrophysical phenomena are time-varying, in the sense that their brightness change over time. In the case of periodic stars, previous approaches assumed that changes in period, amplitude, and phase are well described by either…
We performed R-band time series observations of the young, metal rich open cluster NGC 2301 for 12 nights in Feb. 2004. B images were also obtained and color magnitude diagrams, having limits of R=19.5 and B=21.5, were produced. Only asmall…
Photometry is the most easily acquired information about supernovae. The light curves constructed from regular imaging provide signatures not only for the energy input, the radiation escape, the local environment and the progenitor stars,…
Hipparcos trigonometrical parallaxes of Mira-type variables have been combined with ground-based angular diameter measurements to derive linear diameters. Of eight stars with ground-based data, six have diameters indicating overtone…
We have investigated the mass loss processes in Long Period Variables, by combining radiative transfer modeling with mid-IR imaging and spectroscopic observations. We find a correlation between variability type and temporal variations in…
This study presents new, high-quality, optical photometric observations of three W UMa type contact binaries. The analysis of the corresponding light curves is made using Djurasevic's inverse problem method. To explain the light curve…
The observational data of the near infrared bands (H and K) have been used for the modeling mean light curves. Also the visual observational data have been fitted the same. The infrared and visual mean light curves were compared. All…
The re-analysis of the data reported by Mateo et al. (1998) allowed us to obtain a partially different set of frequencies for the 20 short period variable stars discovered in the Carina dSph galaxy. They are subdivided into 6…
Stars exhibit a bewildering variety of variable behaviors ranging from explosive magnetic flares to stochastically changing accretion to periodic pulsations or rotations. The principal LSST surveys will have cadences too sparse and…
The light scattered by an extrasolar Earth-like planet's surface and atmosphere will vary in intensity and color as the planet rotates; the resulting light curve will contain information about the planet's properties. Since most of the…
We present optical lightcurves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey. Using data from the Mosaic-II instrument on the Blanco 4m…
The temperature of a circumbinary disc edge should undulate due to variations in illumination as a function of binary orbital phase. We explore circumbinary disc temperature variations as a source of broad-band infrared light curve…
We present results from a comparative study of light curves of Cepheid and RR Lyrae stars in the Galaxy and the Magellanic Clouds with their theoretical models generated from the stellar pulsation codes. Fourier decomposition method is used…
Robust fast methods to classify variable light curves in large sky surveys are becoming increasingly important. While it is relatively straightforward to identify common periodic stars and particular transient events (supernovae, novae,…
We investigate the question whether there is a real difference in the light change between stars classified as semiregular (SRV) or irregular (Lb) variables by analysing photometric light curves of 12 representatives of each class. Using…