Related papers: Long-period variables in NGC147 and NGC185

As part of our ongoing study of the evolved giants in the galactic halo, we consider the sample of 1286 long-period variables (LPVs) in the southern hemisphere provided by the Catalina Sky Survey experiment. These LPVs have periods P larger…

The near and mid-infrared characteristics of large amplitude, Mira, variables in Local Group dwarf irregular galaxies (LMC, NGC 6822, IC 1613, Sgr dIG) are described. Two aspects of these variables are discussed. First, the short period (P…

Long secondary period (LSP) variable stars are a subclass of long-period variables (LPV) that exhibit additional long-term variability alongside pulsations. Despite being observed in over 30% of LPVs, the reason behind the LSP phenomenon is…

We used four-year baseline HST/WFC3 IR observations of the Galactic Centre in the F153M band (1.53 micron) to identify variable stars in the central ~2.3'x2.3' field. We classified 3845 long-term (periods from months to years) and 76…

Context: The period-luminosity diagram (PLD) has proven to be a powerful tool for studying populations of pulsating red giants. Gaia Data Release 2 (DR2) provides a large data set including many long-period variables (LPVs) on which this…

We are re-analyzing the MACHO variable star database to explore the relationships between pulsation, evolution, and mass loss in evolved stars. We will analyze the multi-periodic properties of long period variable (LPV) stars, 50% of which…

The population of nearby dwarf galaxies in the Local Group constitutes a complete galactic environment, perfect suited for studying the connection between stellar populations and galaxy evolution. In this study, we are conducting an optical…

We present the results of a photometric survey for variable stars in the central region of the nearby globular cluster NGC 6397.Time series photometry was obtained for 30 variable objects. The sample includes 12 new objects, of which 6 show…

We present the first cross-identifications of sources in the near-infrared DENIS survey and in the micro-lensing EROS survey in a field of about 0.5 square degrees around the optical center (OC) of the Large Magellanic Cloud. We analyze the…

We exploit data from the Pan-Andromeda Archaeological Survey (PAndAS) to study the extended structures of M31's dwarf elliptical companions, NGC147 and NGC185. Our wide-field, homogeneous photometry allows to construct deep colour-magnitude…

The absolute K magnitudes and kinematic parameters of about 350 oxygen-rich Long-Period Variable stars are calibrated, by means of an up-to-date maximum-likelihood method, using Hipparcos parallaxes and proper motions together with radial…

In this second paper on our variability survey of central stars of planetary nebulae (CSPNe) using ZTF, we report 11 long-timescale variables with variability timescales ranging from months to years. We also present preliminary analyses…

Long period variable stars arise in the final stages of the asymptotic giant branch phase of stellar evolution. They have periods of up to ~1000d and amplitudes that can exceed a factor of three in the I-band flux. These stars pulsate…

We present the results of our search for variable stars using the long-term Las Cumbres Observatory (LCO) monitoring of white dwarf ZTF J0139+5245 with the two 1.0-m telescope nodes located at McDonald Observatory using the Sinistro imaging…

The $13.6\times 13.6$ arcmin$^{2}$ field covering the central part of the globular cluster NGC~6397 was surveyed in a search for short-period variable stars. We obtained light curves for 6 close binaries, 2 SX~Phe stars and 1 RR~Lyrae…

We analysed the light curves of a large sample of long period variables in the LMC from the AGAPEROS catalogue. The (non)regularity of the light change is discussed in detail showing that the majority of the light curves cannot be described…

With the help of model calculations we aim at reproducing the observational photometric findings for a large sample of well-characterised galactic C-type Mira variables losing mass at different rates. We used dynamic model atmospheres,…

We report here CCD $I$-band time-series photometry of a young (2$-$5 Myr) cluster NGC 2282 to identify and understand the variability of pre-main-sequence (PMS) stars. The $I$-band photometry, down to $\sim$ 20.5 mag, enables us to probe…

We present the detection of a variable star with an $18.05$ minute period in far-ultraviolet (FUV) images of the globular cluster NGC 1851 taken with the Hubble Space Telescope (HST). A candidate optical counterpart lies on the red…

Stars in the Asymptotic Giant Branch (AGB) phase, dominated by low to intermediate-mass stars in the late stage of evolution, undergo periodic pulsations, with periods of several hundred days, earning them the name Long Period Variables…