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New variable sources revealed by DECam toward the LMC: The first 15 deg2
Nucita, A. A.; De Paolis, F.; Franco, A. +2 more
The Dark Energy Camera (DECam) is a sensitive, wide field instrument mounted at the prime focus of the 4 mV. Blanco Telescope in Chile. Beside its main objectives, i.e. understanding the growth and evolution of structures in the Universe, the camera offers the opportunity to observe a ∼ 3deg2 field of view in one single pointing and, wi…
Analysis of the B-stars in field of the solar neighborhood young open cluster IC 2391 using UVES spectra and Gaia DR3
Hendy, Y. H. M.; El-Depsey, M. H.; Shokry, Ahmed +2 more
In this paper, we present the stellar parameters of individual B-type stars in the IC 2391 young open cluster, using the Barbier-Chalonge-Divan (BCD) Spectrophotometry System, to obtain stellar fundamental parameters from direct measurements of the Balmer discontinuity. This method is optimally suited for late B-stars to determine stellar fundamen…
First photometric study of three eclipsing binary star systems: V495 Aur, V589 Aur and V478 Cam
Erdem, Ahmet; Öztürk, Oğuz
The light curve solutions and orbital period analysis of V495 Aur, V589 Aur and V478 Cam eclipsing binary star systems are presented for the first time in this study. Transiting Exoplanet Survey Satellite (TESS) observations were used as observational data. From the light curve solutions, it was concluded that all three systems are semi-detached b…
X-ray and optical observations of two AM Her type cataclysmic variables: V388 Peg and V1189 Her
Zengi̇n Çamurdan, Dicle
We present time-resolved photometry of a polar V388 Peg and a strong candidate polar V1189 Her observed by T100 telescope at TÜBİTAK National Observatory between June-August 2014 and their X-ray observations using Swift archival data obtained in Apr 2014 (V388 Peg) and in Nov 2011 (V1189 Her). These data were supplemented by archival CRTS, ZTF, AS…
Possible merger signatures of the bulges of non-dwarf galaxies in the core of the Coma Cluster
Hasan, S. N.; Poloji, Nagamani; Hasan, Priya
In this paper, we discuss a method to study virialised clusters of galaxies with no-interaction features, like tails and bridges, using diagnostics of bulge classification and their properties, namely Sérsic index (n) and the Kormendy relation. We study a sample of non-dwarf galaxies in the core of the Coma Cluster using HST/ACS data. We divided o…
Study of five eccentric eclipsing binary systems
Zejda, M.; Auer, R. F.; Kolář, J.
In this paper we present the comprehensive analysis of five binary systems: GX Lac, TT Lyr, OGLE LMC-ECL-7641, OGLE LMC-ECL-17660, and OGLE LMC-ECL-17411. With new photometric observations combined with other available data mostly from TESS, MACHO, and OGLE, we calculated new minima timings and study the O - C diagrams. We fitted the light curves …
Catalog of spiral arm tangents (Galactic longitudes) in the Milky Way, and the age gradient based on various arm tracers
Vallée, Jacques P.
An updated catalog of 205 observed tangents to the spiral arms (in Galactic longitudes) since 1980 is presented. This represents an addition of 80 arm tangents in 6 years (since 2016). Most arm tangents are observed at telescopes in the radio régime.
In this study, the separation of each arm tracer from the dust lane is analysed to obtain the…First photometric and orbital period investigations of the total-eclipse contact binary V0339 Com
Yu, Yun-Xia; Hu, Ke; Xiang, Fu-Yuan +2 more
We presented the first photometric and orbital period investigation for the W UMa-type binary V0339 Com. The multi-bands light curves were obtained and analyzed with the Wilson-Devinney Code. The photometric solutions suggested that V0339 Com is an A-subtype shallow contact binary with a degree of contact f = 12 . 0% . The total eclipse of V0339 C…
Absolute parameters of four W UMa stars with extreme low mass ratios
Popov, Velimir A.; Petrov, Nikola I.
Photometric observations of four extreme low mass ratio W UMa binaries with wide total eclipses, and their absolute parameters are presented. The main results are as follows: (i) ASAS J015429+2042.8 is of A subtype while V755 Cep, VESPA V22 and GSC 02800-01387 are of W subtype; (ii) The mass ratios are close to the lower mass-ratio limit and can b…
On the Sun's distance from the center and the shape of the inner halo in the Galaxy: Gaia EDR3, HST and literature globular clusters
Gedalin, Michael; Jiang, Ing-Guey; Griv, Evgeny
A statistical method is used to derive both the Sun's distance r0 from the Galactic Center (GC) and the 3D geometry of the inner (< 25 kpc) halo. The spatial distribution of the 138 Gaia EDR3 globular clusters (GCs) with distances established on a combination of HST and literature data of Baumgardt and Vasiliev (2021) is explored. An…