Related papers: Discovery of a rapidly pulsating subdwarf B star c…
Blue Large-Amplitude Pulsators (BLAPs) are rare short-period ($\lesssim$80 min) pulsating variable stars exhibiting large-amplitude brightness variations (typically between 0.1 and 0.4 mag). As a recently discovered class of radial-mode…
The O- and B-type (OB-type) pulsating stars are important objects to study the structure and evolution of massive stars through asteroseismology. A large amount of data from various sky surveys provide an unprecedented opportunity to search…
The magnetic beta Cep pulsator xi^1 CMa has the longest rotational period of any known magnetic B-type star. It is also the only magnetic B-type star with magnetospheric emission that is known to be modulated by both rotation and pulsation.…
The third Gaia data release provides photometric time series covering 34 months for about 10 million stars. For many of those stars, a characterisation in Fourier space and their variability classification are also provided. This paper…
We search for new variable B-type pulsators in the CoRoT data assembled primarily for planet detection, as part of CoRoT's Additional Programme. We aim to explore the properties of newly discovered B-type pulsators from the uninterrupted…
We present the recent discovery of a new subdwarf B variable (sdBV), with an exceptionally low surface gravity. Our spectroscopy of J20136+0928 places it at Teff = 32100 +/- 500, log(g) = 5.15 +/- 0.10, and log(He/H) = -2.8 +/- 0.1. With a…
We present the analysis of existing optical photometry and new optical spectroscopy of the candidate cataclysmic variable star OGLE-BLG504.12.201843. As was shown previously, this object has an orbital period of 0.523419 days and exhibits…
The identification of non-radial g-mode oscillations as the cause of variability in cool subdwarf B stars (PG1716 variables) has been frustrated by a 5 000 K discrepancy between the observed and theoretical blue edge of the instability…
In this paper we present time series photometry of 104 variable stars in the cluster region NGC 1893. The association of the present variable candidates to the cluster NGC 1893 has been determined by using $(U-B)/(B-V)$ and $(J-H)/(H-K)$…
The survey phase of the Kepler Mission includes a number of hot subdwarf B (sdB) stars to search for nonradial pulsations. We present our analysis of two sdB stars that are found to be g-mode pulsators of the V1093 Her class. These two…
The globular cluster omega Centauri contains the largest known population of very hot horizontal branch (HB) stars. We have used the Hubble Space Telescope to obtain a far-UV/optical color-magnitude diagram of three fields in omega Cen. We…
The hot subdwarf B (sdB) stars form an homogeneous group populating an extension of the horizontal branch (HB) in the ($T_{\rm eff}$--$\log g$) diagram towards temperatures up to 40,000 K. The recent discovery that many of them are…
We report the classification of 24 puzzling short-period variable stars located in OGLE-IV Galactic bulge fields. The stars are low-amplitude (<0.05 mag) multi-periodic objects with dominant periods between 22 and 54 min whose type could…
The field of the globular cluster M10 (NGC 6254) was monitored between 1998 and 2015 in a search for variable stars. V -light curves were derived for 40 variables or likely variables, most of which are new detections. Proper motions…
Until very recently the physical mechanism driving oscillations in $\beta$~Cep and other early type stars has been a mystery. The breakthrough came with the publication of new OPAL and OP opacity data. Model calculations with the new…
From the Fourier analysis of the catalogue of ~200,000 variable candidates in the OGLE-II Galactic fields, we found a sample of about 230 short-period low-amplitude variable stars. From their position in the colour-magnitude diagram and the…
In this work, we studied the variable stars in the open cluster NGC 1912 based on the photometric observations and $Gaia$ DR2 data. More than 3600 CCD frames in B, V, R filters were reduced, and we obtained the light curves that span about…
About 22000 Kepler stars and nearly 60000 TESS stars from sectors 1-24 have been classified according to variability type. A large proportion of stars of all spectral types appear to have periods consistent with the expected rotation…
We report BRITE-Constellation photometry of the beta Cep pulsator xi 1 CMa. Analysis of these data reveals a single pulsation period of 0.2095781(3) d, along with its first and second harmonics. We find no evidence for any other…
Blue Large-Amplitude Pulsators (BLAPs) are a new class of pulsating variable star. They are located close to the hot subdwarf branch in the Hertzsprung-Russell diagram and have spectral classes of late O or early B. Stellar evolution models…