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Related papers: CzeV - The Czech Variable Star Catalogue

200 papers

We have performed a search for variable stars in the dwarf irregular galaxy NGC 6822 using wide-field multi-epoch VI photometry down to a limiting magnitude $V$ $\sim$ 22. Apart from the Cepheid variables in this galaxy already reported in…

Astrophysics · Physics 2009-11-11 R. E. Mennickent , W. Gieren , I. Soszynski , G. Pietrzynski

We report the results of a time-series CCD photometric survey of variable stars in the field of the open cluster NGC 2126. In about one square degree field covering the cluster, a total number of 21 variable candidates are detected during…

Solar and Stellar Astrophysics · Physics 2009-07-22 Shun-Fang Liu , Zhen-Yu Wu , Xiao-Bin Zhang , Jiang-Hua Wu , Jun Ma , Zhao-Ji Jiang , Jian-Sheng Chen , Xu Zhou

The study of open clusters and their short period variable stars is fundamental in stellar evolution. Because the cluster members are formed in almost the same physical conditions, they share similar stellar properties such age and chemical…

Solar and Stellar Astrophysics · Physics 2011-11-07 J. H. Peña , L. Fox-Machado , H. García , A. Rentería , E. Romero , S. Skinner , A. Espinosa

The All-Sky Automated Survey for Supernovae (ASAS-SN) is the first optical survey to routinely monitor the whole sky with a cadence of $\sim2-3$ days down to V$\lesssim17$ mag. ASAS-SN has monitored the whole sky since 2014, collecting…

We present results of star variability analysis in OGLE II first bulge field. Photometric database was derived by means of image subtraction method (Wozniak 2000) and contains 4597 objects pre-classified as variables. We analyzed all the…

Astrophysics · Physics 2007-05-23 Tomasz Mizerski , Michal Bejger

The variable stars in the VSX catalog are derived from a multitude of inhomogeneous data sources and classification tools. This inhomogeneity complicates our understanding of variable star types, statistics, and properties, and it directly…

The number of discovered TeV sources populating the extragalactic sky in 2017 is nearly 70, mostly blazars located up to a redshift ~1. Ten years ago, in 2007, less than 20 TeV emitters were known, up to a maximum redshift of 0.2. This is a…

High Energy Astrophysical Phenomena · Physics 2017-07-06 Elisa Prandini

We report the discovery of eleven new variable DA white dwarf (ZZ Ceti) stars. Candidates were selected by deriving temperatures from model fits to spectra obtained from the Sloan Digital Sky Survey. We also find objects whose temperatures…

We present preliminary results of the first near-infrared variability study of the Arches cluster, using adaptive optics data from NIRI/Gemini and NACO/VLT. The goal is to discover eclipsing binaries in this young (2.5 $\pm$ 0.5 Myr),…

Solar and Stellar Astrophysics · Physics 2011-08-24 K. Markakis , A. Z. Bonanos , G. Pietrzynski , L. Macri , K. Z. Stanek

The analysis of non-variable stars is generally neglected in the literature. However, such objects are needed for many calibration processes and for testing pulsational models. The photometric time series of the Kepler satellite mission…

We present the results of an automated variability analysis of the Kepler public data measured in the first quarter (Q1) of the mission. In total, about 150 000 light curves have been analysed to detect stellar variability, and to identify…

Solar and Stellar Astrophysics · Physics 2015-05-27 J. Debosscher , J. Blomme , C. Aerts , J. De Ridder

We have analysed the photometric data obtained with the STEREO spacecraft for 558 non-magnetic chemically peculiar (CP) stars to search for rotational and pulsational variability. Applying the Lomb-Scargle and the phase dispersion…

Solar and Stellar Astrophysics · Physics 2015-06-12 E. Paunzen , K. T. Wraight , L. Fossati , M. Netopil , G. J. White , D. Bewsher

Using light curves from the HATNet survey for transiting extrasolar planets we investigate the optical broad-band photometric variability of a sample of 27,560 field K and M dwarfs selected by color and proper-motion. A total of 2120 stars…

Solar and Stellar Astrophysics · Physics 2011-02-04 J. D. Hartman , G. Á. Bakos , R. W. Noyes , B. Sipöcz , G. Kovács , T. Mazeh , A. Shporer , A. Pál

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…

Astrophysics · Physics 2009-11-06 L. L. Kiss , Gy. Szabo , K. Sziladi , G. Furesz , K. Sarneczky , B. Csak

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…

We present high precision CCD photometry of 1791 objects in 20 open clusters with an age from 10 Myr to 1 Gyr. These observations were performed within the Delta a photometric system which is primarily used to detect chemically peculiar…

Astrophysics · Physics 2009-11-10 E. Paunzen , K. Zwintz , H. M. Maitzen , O. I. Pintado , M. Rode-Paunzen

The first catalog of chromospherically active and ellipsoidal variable stars in the OGLE database is presented. The periods, the observed magnitudes and colors, their values free of interstellar extinction, and Fourier coefficients of light…

Astrophysics · Physics 2016-08-30 Arkadiusz Olech

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,…

Solar and Stellar Astrophysics · Physics 2015-06-03 K. T. Wraight , L. Fossati , M. Netopil , E. Paunzen , M. Rode-Paunzen , D. Bewsher , A. J. Norton , G. J. White

We present an automated classification of stars exhibiting periodic, non-periodic and irregular light variations. The Hipparcos catalogue of unsolved variables is employed to complement the training set of periodic variables of Dubath et…

With the advent of surveys generating multi-epoch photometry and the discovery of large numbers of variable stars, the classification of these stars has to be automatic. We have developed such a classification procedure for about 1700 stars…

Astrophysics · Physics 2009-11-10 L. Eyer , C. Blake