Related papers: SPB stars in the open SMC cluster NGC 371
One hundred and forty six long-period red variable stars in the Large Magellanic Cloud (LMC) from the three year MOA project database were analysed. A careful periodic analysis was performed on these stars and a catalogue of their…
The Small Magellanic Cloud (SMC) has recently been found to harbour more than two hundred per cent increase of its known cluster population. We provide here with solid evidence that such an unprecedented number of clusters could be largely…
Semi-convection is a slow mixing process in chemically-inhomogeneous radiative interiors of stars. In massive OB stars, it is important during the main sequence. However, the efficiency of this mixing mechanism is not properly gauged yet.…
We report seismic analyses of five pulsating subdwarf B (sdBV) stars observed during Kepler's K2 mission, each with a white dwarf companion. We find three of the five to be g-mode-dominated hybrid pulsators. For the other two, we only…
We propose to observe with Kepler an age sequence of nearby uncrowded open clusters. The current Kepler field contains very few (only 4) somewhat distant and/or old clusters. Nearby open clusters are already well characterized from ground-…
We present high S/N integrated spectra of 24 star clusters in the LMC obtained using the FLAIR spectrograph at the UK Schmidt. The spectra have been placed onto the Lick/IDS system in order to test the calibration of Simple Stellar…
We present a survey of variable stars detected in K2 Campaign 13 within the massive intermediate age ($\sim1$ Gyr) open cluster NGC 1817. We identify a complete sample of 44 red clump stars in the cluster, and have measured asteroseismic…
We present a comprehensive photometric analysis of a young open cluster NGC 1960 (M36) along with the long-term variability study of this cluster. Based on the kinematic data of Gaia DR2, the membership probabilities of 3871 stars are…
We present a variability study of 4646 massive stars in the Small Magellanic Cloud (SMC) with known spectral types from the catalog of Bonanos et al. (2010) using the light curves from the OGLE-III database. The goal is to exploit the time…
Accurate CCD observations of three Cepheids in the SMC were made with the purpose of confirming their nature of second overtone mode Cepheids. The stars were suspected pulsating in the second overtone mode owing to the unusual light curve…
The majority of magnetic chemically peculiar (mCP) stars exhibit periodic light, magnetic, radio, and spectroscopic variations that can be adequately modelled as a rigidly-rotating main-sequence star with persistent surface structures.…
Delta Scuti ($\delta$ Sct) stars have been extensively studied in our Galaxy, but far less in extragalactic systems. Here we study the population of $\delta$ Sct variables in NGC 419, an intermediate-age globular cluster of the Small…
This is a catalogue of approximately 70 X-ray emitting binary systems in the Small Magellanic Cloud (SMC) that contain a Be star as the mass donor in the system and a clear X-ray pulse signature from a neutron star. The systems are…
As a result of the search among about 11 000 stars from the public ASAS-3 database, we report detection of pulsating components in eleven eclipsing binaries. In particular, we have found three classical Algols, MX Pav, IZ Tel, and VY Mic,…
V-band time-series CCD photometric observations of the intermediate-age open cluster M11 were performed to search for variable stars. Using these time-series data, we carefully examined light variations of all stars in the observing field.…
We report the results of our search for magnetic fields in a sample of 16 field Be stars, the binary emission-line B-type star upsilon Sgr, and in a sample of fourteen members of the open young cluster NGC3766 in the Carina spiral arm. The…
We have conducted a deep ($15 \la r \la 23$), 20 night survey for transiting planets in the intermediate age ($\sim 550 {\rm Myr}$) open cluster M37 (NGC 2099) using the Megacam wide-field mosaic CCD camera on the 6.5m Multiple Mirror…
High-mass binary stars are known to show an unexplained discrepancy between the dynamical masses of the individual components and those predicted by models. In this work, we study Sigma Scorpii, a double-lined spectroscopic binary system…
A CCD photometric study of the dense galactic open cluster M37 is presented and discussed. The majority of the analysed data are time-series measurements obtained through an R_C filter. The observations were carried out on seven nights…
(abridged)Variability is a key property of stars on the asymptotic giant branch (AGB). Their pulsation period is related to the luminosity and mass-loss rate of the star. The long-period variables (LPVs) and Mira variables are the most…