Results 1 to 10 of about 136,231 (311)

An Optically Discovered Outburst from XTE J1859+226

open access: yesThe Astrophysical Journal, 2023
Using the Zwicky Transient Facility, in 2021 February we identified the first known outburst of the black hole X-ray transient XTE J1859+226 since its discovery in 1999. The outburst was visible at X-ray, UV, and optical wavelengths for less than 20 days,
Eric C. Bellm   +15 more
doaj   +1 more source

Parameters and Pulsation Constant of Cepheid

open access: yesParticles, 2023
The analysis of fifty empirical period-radius relations and forty-three empirical period-luminosity relations is performed for the Cepheids. It is found that most of these relations have significant systematic errors.
Sergei V. Sinitsyn
doaj   +1 more source

Streaming classification of variable stars [PDF]

open access: yesMonthly Notices of the Royal Astronomical Society, 2019
ABSTRACTIn the last years, automatic classification of variable stars has received substantial attention. Using machine learning techniques for this task has proven to be quite useful. Typically, machine learning classifiers used for this task require to have a fixed training set, and the training process is performed offline.
Zorich, L   +2 more
openaire   +3 more sources

Variability in NGC 3201 Giant Stars

open access: yesThe Astronomical Journal, 2023
We present the analysis of 510 light curves in V and I bands of 255 giant stars in the globular cluster NGC 3201. Our aim is to expand the sample of new types of variables reported in a previous study. These variables show a short period ( P _V < 0.6 day)
C. C. Cortés   +4 more
doaj   +1 more source

Cataclysmic Variable Stars [PDF]

open access: yesInternational Astronomical Union Colloquium, 1984
AbstractThe properties of cataclysmic variable outbursts are reviewed, and interpreted in terms of dynamical instabilities by the red component, and subsequent evolution of the white dwarf accretion disc subject to a mass transfer burst in the transfer stream.
openaire   +1 more source

Future of the General Catalogue of Variable Stars from the Experience of Recent Name-lists

open access: yesOpen Astronomy, 2021
We briefly outline the history of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variable Stars (NSV catalogue). Recently, we have completed a revision of the NSV catalogue.
Samus Nikolay N.   +5 more
doaj   +1 more source

Semiregular Variable Stars [PDF]

open access: yesAstrophysics, 2019
19pages, in Ukrainian, 5 figures, 4 ...
openaire   +2 more sources

HD 66051, an eclipsing binary hosting a highly peculiar, HgMn-related star

open access: yesScientific Reports, 2017
HD 66051 is an eclipsing system with an orbital period of about 4.75 d that exhibits out-of-eclipse variability with the same period. New multicolour photometric observations confirm the longevity of the secondary variations, which we interpret as a ...
Ewa Niemczura   +6 more
doaj   +1 more source

Using APASS and 2GSS for studying variable stars

open access: yesEPJ Web of Conferences, 2017
The AAVSO Photometric All-Sky Survey (APASS) provides calibrated magnitudes in the range 7 < V < 17 for the entire sky, in the BVugriZsY bandpasses. While primarily designed for 0.02 mag calibration, it provides photometry over a many-year baseline, and ...
Henden Arne   +5 more
doaj   +1 more source

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