Search Publications
Revised Orbital Parameters of Beaming Eclipsing Binary System HV Cnc from Kepler Photometry
Gürol, Birol; Gökay, Gökhan; Özdemir, Sacit
High precision photometry gathered from Kepler database and radial velocity measurements of the HV Cnc system found in the literature were simultaneously analyzed by the Wilson-Devinney (WD) code to better understand system parameters. Some physical quantities needed by the WD code in iterations, such as limb darkening coefficients, Kurucz's model…
Study of open cluster King 13 using CCD VI, 2MASS and Gaia DR2 Astrometry.
Bisht, D.; Rangwal, Geeta; Yadav, R. K. S. +2 more
In this paper, we present astrophysical parameters of the open cluster King 13 based on the VI CCD and 2MASS JHKs photometric data. This is a poorly studied cluster, for which new results have been found in the present work. To identify probable members, we use proper motion data from Gaia DR2 catalogue. The mean proper motion of the cl…
Multi-wavelength study in the region of IRAS 16571-4029 and 16575-4023 sources
Baume, G.; Borissova, J.; Ramirez Alegria, S. +2 more
We studied the stellar populations and their associated interstellar medium structures located in the region of IRAS 16571-4029 and 16575-4023 sources, aiming to evaluate their distance and their main physical parameters. We focused our attention on the embedded cluster DBS 113 and its associated HII region RCW 116B.
For the study, optical im…A new photometric study of T Tauri stars in the infrared
Chen, P. S.; Liu, J. Y.; Shan, H. G.
We have compiled infrared photometric data from the literature of practically all T Tauri stars found up to date including 444 classical T Tauri stars (CTTSs), 1698 weak-line T Tauri stars (WTTSs) and 1258 not classified T Tauri stars (3400 in total) in addition to 196 post-T Tauri stars (PTTSs). From this data bank we extract the infrared charact…
Variable stars in Palomar 13; an evaporating globular cluster
Arellano Ferro, A.; Muneer, S.; Giridhar, Sunetra +3 more
We present new CCD VI photometry of the distant globular cluster Pal 13. Fourier decomposition of the light curves of the three cluster member RRab stars lead to estimations of [Fe/H] = -1.65, and a distance of 23.67 ± 0.57 kpc. Light and colour near minimum phases for RRab stars leads to an estimate of E(B - V) = 0.104 ± 0.001. A V /(V - I) colou…
Effect of low anisotropy on cosmological models by using supernova data
Hossienkhani, H.; Yousefi, H.; Azimi, N.
By using the supernovae type Ia (SNIa) data we study influence of the anisotropy (although low) on the evolution of the universe and compare ΛCDM model with 6 representative parametrizations of the recent Hubble expansion history H(z). To compare these models we use the maximum likelihood method for find that the best fit dynamical w(z) and q(z) o…
PPMXL and Gaia morphological analysis of Melotte 22 (Pleiades) and Melotte 25 (Hyades)
Elsanhoury, W. H.; Nouh, M. I.
In this article, we present a morphological study of two extended open clusters in the sky, Melotte 22 and Melotte 25 using J, H, and Ks photometry with Gaia DR2 and PPMXL proper motions. Various photometric and kinematic astrophysical parameters have been determined.
Based on proper motions of these clusters, we extract our member…Analysis of a detached eclipsing binary at near the turnoff point of the open cluster NGC 6791 in Kepler field
Çakırlı, Ö.; Dervişoğlu, A.; Yontan, T. +2 more
We analyzed high-precision Kepler photometry and high-resolution UVES and GIRAFFE spectroscopy from ESO Science Archieve for a double-lined eclipsing binary star in the field of the high metallicity old open cluster NGC 6791. Earlier measurements of the masses and radii of the detached system were not accurate enough for photometric and spectrosco…
Photometric observations of the W UMa stars CSS J113505.5+332031, ASAS J142124+1813.1 and HR Boo
Michel, R.; Kjurkchieva, D.
Multicolor photometric observations of the W UMa binaries CSS J113505.5+332031, ASAS J142124+1813.1 and HR Boo are presented. They led to improvement of the orbital periods of CSS J113505.5+332031 and HR Boo. The light curve solutions revealed that all the targets are overcontact binaries with moderate fill-out factors whose components are of G an…
Variable absorption line in XTE J1810-197
Göğüş, Ersin; Güver, Tolga; Vurgun, Eda +1 more
We report the results of a long-term spectral and timing study of the first transient magnetar, XTE J1810-197 which was discovered in 2003, when its X-ray luminosity increased ≈ 100 fold. We fit X-ray spectra of all archival X-ray observations using a two-component blackbody model, where the cool component is most likely originating from the whole…