Related papers: VELOcities of CEpheids (VELOCE) II. Systematic Sea…
We apply the image subtraction method to re-analyze the ESO Very Large Telescope data on M83 (NGC 5236), obtained and analyzed by Thim et al. Whereas Thim et al. found 12 Cepheids with periods between 12-55 days, we find 112 Cepheids with…
In the second part of the OGLE-III Catalog of Variable Stars (OIII-CVS) we present 197 type II Cepheids and 83 anomalous Cepheids in the Large Magellanic Cloud (LMC). The sample of type II Cepheids consists of 64 BL Her stars, 96 W Vir…
Context. This work is part of a long-term spectroscopic study of a sample of 30 multiple stars with early-type components. In this second paper we present the results of six multiple systems in which new stellar components have been…
Type II Cepheids (T2Cs) are radially pulsating variables that trace old stellar populations and provide distance estimates through their period-luminosity (PL) relation. We trace the structure of old stars in the Bulge using new distance…
In an effort to improve our understanding of the spiral arm structure of the Milky Way, we use Classical Cepheids (CCs) to increase the number of young tracers on the far side of the Galactic disk with accurately determined distances. We…
We present the analysis of photometric and spectroscopic data of two bright Galactic Cepheids, X Puppis and XX Sagittarii. Based on the available data in the literature as well as own observations spanning 75 years, we conclude that both…
Based on observations of NGC 300, obtained with the Wide-Field Camera at the 2.2 m ESO/MPI telescope during 29 nights spread over a 5.3 month interval, 117 Cepheids and 12 Cepheid candidates were found which cover the period range from 115…
We aim to investigate the IR excess of 45 MW Cepheids combining different observables to constrain the presence of CSE. We used the SPIPS algorithm, a robust implementation of the parallax-of-pulsation method that combines photometry,…
We present CCD phase-binned light curves at 490 nm for 97 Cepheid variable stars in the bar of the LMC. The photometry was obtained as part of the French EROS project and has excellent phase coverage, permitting accurate decomposition into…
The results of a CCD survey for variability of stars in the nearby galaxy NGC 6822 are presented. The goal of the survey was to obtain good light curves of Cepheids for Fourier decomposition and to detect shorter period Cepheids. Since the…
It is now clear that binarity plays a crucial role in many aspects of planetary nebulae (PNe), particularly the striking morphologies they exhibit. To date, there are ~60 known bCSPNe. However, both theory and observation indicates that…
Recent studies of massive binaries with putative black hole companions have uncovered a phase of binary evolution that has not been observed before, featuring a bloated stripped star that very recently ceased transferring mass to a…
We present the discovery and CCD observations of the first eclipsing binary with a Type II Cepheid component in our Galaxy. The pulsation and orbital periods are found to be 4.1523 and 51.38 days, respectively, i.e. this variable is a…
We present here a new major part of the OGLE Collection of Variable Stars - OGLE Collection of Galactic Cepheids. The new dataset was extracted from the Galaxy Variability Survey images - a dedicated large-scale survey of the Galactic disk…
BVR light curves and radial velocities for the double-lined eclipsing binary V1135\,Her were obtained. The brighter component of V1135\,Her is a Cepheid variable with a pulsation period of 4.22433$\pm$0.00026 days. The orbital period of the…
State-of-the art photometric measurements of extragalactic Cepheids account for the mean additional light due to chance superposition of Cepheids on crowded backgrounds through the use of artificial star measurements. However, light from…
We present the analysis of a peculiar W~Virginis (pWVir) type-II Cepheid, OGLE-LMC-T2CEP-211 ($P_{puls}=9.393\,d$), in a double-lined binary system ($P_{orb}=242\,d$), which shed light on virtually unknown evolutionary status and structure…
We analyse photometry for 138 first overtone Cepheids from the Small Magellanic Cloud, in which Optical Gravitational Lensing Experiment (OGLE) team discovered additional variability with period shorter than first overtone period, and…
We are conducting a long-term photometric survey of the nearby galaxy M33 to discover Cepheids, eclipsing binaries, and long-period variables. The dataset combines previously-obtained optical images from the DIRECT project with new…
We present the results of spectroscopic observations of two eclipsing WR+OB-type systems - CQ Cep and CX Cep, performed in 2020-2023 with a low-resolution slit spectrograph TDS ($\lambda\lambda= 3660-7410$\AA, $R = 1300-2500$) on 2.5-m…