Search Publications
Global parameters of the totally-eclipsing W UMa stars NSVS 6673994, NSVS 4316778, PP Lac and NSVS 1926064
Popov, Velimir A.; Petrov, Nikola I.; Kjurkchieva, Diana P.
Photometric observations of four totally-eclipsing W UMa binaries, NSVS 6673994, NSVS 4316778, PP Lac and NSVS 1926064, are presented. Their global parameters were determined from the light curve solutions and GAIA distances. The main results are as follows: (i) NSVS 6673994, NSVS 4316778 and PP Lac are of W subtype while NSVS 1926064 is of A subt…
Enhancing coronal structures with radial local multi-scale filter
Ji, Kaifan; Bai, Xianyong; Liu, Hui +2 more
Images of the corona contain information over a wide range of spatial scales and various structures such as coronal holes, coronal loops, coronal mass ejections (CMEs), and helmet streamers with differences in brightness. Therefore, processing these images is important for determining various types of information. However, it is very difficult to …
Photometric study and kinematics of the EL CVn type eclipsing binary: WASP 1628+10
Luo, Yangping
1SWASP J162842.31+101416.7 (WASP 1628+10) is an EL CVn-type eclipsing binary system that is composed of a very low mass helium white dwarf precursor (WSAP 1628+10B) and an A-type dwarf star (WASP 1628+10A). We presented time-series BV photometric observations of WASP 1628+10. Six times of light minima were observed. The physical parameters of the …
New CCD photometry and light curve analysis of two WUMaBinaries: 1SWASP J133417.80+394314.4 and V2790 Orion
El-Depsey, M. H.; Hassan, I. A.; Shokry, A. +5 more
We present a new multicolor CCD photometry and light curve analysis of two eclipsing binary systems, 1SWASP J133417.80 + 394314.4 and V2790 Orion. The photometric solutions for both binaries were carried out using the updated version of the Wilson- Devinney code. The results showed that first systems is A- type W UMa with mass ratios q = 0.158 whi…
Light curve analysis of ground-based data from exoplanets transit database
Poro, A.; Davoudi, F.; Khakpash, S. +9 more
Photometric observations of exoplanet transits can be used to derive the orbital and physical parameters of an exoplanet. We analyzed several transit light curves of exoplanets that are suitable for ground-based observations whose complete information is available on the Exoplanet Transit Database (ETD). We analyzed transit data of planets includi…
Miscellaneous photometric variations in cataclysmic variables: V455 And, SS Cyg, AQ Men, LQ Peg, RW Tri and UX UMa
Bruch, Albert
Cataclysmic variables are among the photometrically most unstable star in the zoo of stellar objects, exhibiting light variations on all time-scales between millennia and seconds. The literature is full of reports on variable phenomena which often require independent confirmation before they can be accepted as established facts. In this contributi…
AG Leonis Minoris-An evolved, detached eclipsing binary
Nelson, Robert H.
Radial velocity data and photometric light curves (in the B. V, and Ic passbands) for the detached eclipsing binary AG Leo Minoris were acquired-apparently for the first time-and are reported here. Roche modelling using the 2003 version of the Wilson-Devinney code was completed, yielding the basic parameters. The period appears to be co…
The characteristics of the coronal mass ejections preceding the associated X-ray and γ-ray burst solar flares
Abdel-Sattar, Walid; Mawad, Ramy
In this study, investigated 14,786 coronal mass ejection (CME) events and 5092 Gamma-ray Burst Monitor (GBM) solar flare events (called γ-ray burst solar flare) recorded during 2008-2017, by using temporal and spatial conditions criteria, we found 845 (about 16%) CME events associated with γ-ray burst solar flare events only (hereafter, CME-γ-pref…
DX Cygni: A triple system with mass transfer
Wolf, M.; Mašek, M.; Kučáková, H. +2 more
A dozen of new precise times of eclipses were measured for the eclipsing binary DX Cygni as a part of our long-term observational project for studying neglected eclipsing binaries with a short orbital period. Based on a current O - C diagram, we found for the first time that its period is increasing (dP / P = 1.68 ×10-7 day/years) and t…
Discovery of deep eclipses in the cataclysmic variable IPHAS J013031.89+622132.3
Kozhevnikov, V. P.
I performed photometric observations of the poorly studied cataclysmic variable IPHAS J013031.89+622132.3 and discovered very deep eclipses. I obtained observations over 14 nights for a total time of 50 hours during a time span of 6 months. Thanks to the long observation interval, I determined the orbital period with high precision, Porb