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Study of an Intermediate Age Open Cluster IC 1434 Using Ground-Based Imaging and Gaia DR2 Astrometry
Bisht, D.; Hendy, Y. H. M.
We present a detailed photometric and kinematical analysis of the poorly studied open cluster IC 1434 using CCD VRI, APASS, and Gaia DR2 database for the first time. By determining the membership probability of stars we identify the 238 most probable members with a probability higher than 60% by using proper motion and parallax data as taken from …
X-Ray Flux and Spectral Variability of BL Lacertae Objects Mrk 421, Mrk 501, and 1ES1426+428 with Suzaku Satellite
Abdelbar, Ahmed M.; Beheary, M. M.; Saad, A. Ata +1 more
We present a detailed spectral study of Suzaku observations of three blazars (Mrk 421, Mrk 501, and 1ES1426+428). The X-ray properties of our sample are derived by extracting the BL Lacertae sample spectra, and fitted by five models. The fit was in the soft X-ray band (0.8 - 10.0 keV). These models give similar results. By comparing the fits from …
Mass Ratios of Long-Period Binary Stars Resolved in Precision Astrometry Catalogs of Two Epochs
Makarov, V. V.
Mass ratios of widely separated, long-period, resolved binary stars can be directly estimated from the available data in major space astrometry catalogs, such as the ESA's Hipparcos and Gaia mission results. The method is based on the universal principle of inertial motion of the system's center of mass in the absence of external forces, and is in…
New Spectral Analysis Results Within the Scope of Extended Matter Research in the AR Lacertae Active Binary System
Ekmekçi, F.; Karakuş, O.
Within the scope of extended matter research, we present new spectral analysis results of an active binary system, AR Lac. The low and high resolution spectra of this system, were taken during the period 2013-2016. The evaluation of low dispersion spectra together with the B, V, Rc, Ic and WISE photometric data showed that AR…