Search Publications
X-ray reprocessing: Through the eclipse spectra of low mass X-ray binaries with XMM-Newton
Paul, Biswajit; Aftab, Nafisa
Eclipsing X-ray binaries make an ideal condition to study reprocessed X-rays, as the X-rays detected during eclipse are purely reprocessed while the much brighter primary X-rays are blocked by the companion star. We carried out a comprehensive study of X-ray reprocessing with four eclipsing Low Mass X-ray Binary (LMXB) systems by comparing X-ray s…
Spectral study of the planetary nebula NGC 2452
Ali, A.; Snaid, S.; Alruhaili, A.
We provide a detailed study for the Galactic planetary nebula (PN) NGC 2452, which has long been suspected to be a member of the Galactic cluster NGC 2453. The present study uses integral field unit (IFU) spectroscopic observations of the PN to explore its physical conditions, chemical abundances, kinematical characteristics, and morphological fea…
Multi-wavelength photometric study of five contact binaries in the field of globular cluster M4
Brosch, Noah; Jagirdar, Rukmini; Devarapalli, Shanti Priya +4 more
Binary stars are believed to be key determinants in understanding globular cluster evolution. In this paper, we present the Multi-band photometric analyses of five variables in the nearest galactic globular cluster M4, from the observations of CASE, M4 Core Project with HST for four variables (V48, V49, V51, and V55) and the data collected from T4…
A and F spectral type runaway star candidates in the 30 Doradus region
Gebrehiwot, Yikdem Mengesha; Teklehaimanot, Berhe Tewelde
The relative proper motions of eight A-F type runaway candidate stars, from the eleven cataloged stars by Platais et al. (2018) in the 30 Doradus (30 Dor) region of the Large Magellanic Cloud (LMC), are investigated using Gaia DR3 data. We cross-matched the coordinates presented by the authors with Gaia DR3 coordinates, and we took only eight star…
Spectroscopic and photometric investigations of the totally eclipsing contact binary V1320 Cas
Li, Kai; Gao, Xing; Liu, Jian-Fei +4 more
We analyzed the light curve of the total eclipse contact binary V1320 Cas, obtained reliable photometric solutions, confirmed it to be a W-type contact binary with a mass ratio of 3.404 and a contact degree of 23.9%, a cool spot is discovered on the less massive component. Orbital period analysis indicates that the period of V1320 Cas is decreasin…
An Investigation of six contact binary systems and a semi-detached one
Popov, Velimir; Acerbi, Francesco; Barani, Carlo +1 more
We present a photometric analysis of six W Ursae Majoris contact binaries and one semi-detached system using multifilter CCD observations. The data were obtained with the 0.25 m Schmidt Cassegrain telescope at the observatory Stazione Astronomica Betelgeuse (SAB) in Magnago, Italy, and the 30-cm Ritchey Chretien Astrograph at the IRIDA observatory…
Unveiling compact planetary nebulae: Broad-band survey analysis and LAMOST confirmation
Gutiérrez-Soto, L. A.; Weidmann, W. A.; Faifer, F. R. +1 more
Planetary nebulae (PNe) are pivotal for advancing our knowledge of stellar evolution and galactic chemical enrichment. Recent progress in surveys and data analysis has revolutionized PN research, leading to the discovery of new objects and deeper insights into their properties. We have devised a novel photometric selection method, integrating GAIA…
A photometric study of a total-eclipse contact binary V458 Mon
Zhu, Liying; Matekov, Azizbek; Zubairi, Ahmed Waqas +3 more
We present light curve solution of V458 Mon firstly by using the Wilson-Devinney code. The total eclipse and deep minima of the light curves of V458 Monenable us to determine reliable orbital parameters of the binary system. The solution suggests that V458 Monis a low mass ratio binary system with about 0.2 possessing a moderate degree of contact.…
Observational constraints on modified CPL models considering non-cold dark matter
Sardar, Gopal; Chakraborty, Subenoy
In the present work we consider three modified Chevallier–Polarski–Linder (CPL) models with considering non-cold dark matter in the background of homogeneous and isotropic FLRW space–time model. From the observational data set ((Pantheon+)+BAO+HST) we find that all the parameters involved in the models having equation of dark energy state ωde=ω0+ω…
Further lunar occultations results from the Trebur Observatory, 2021–24
Ohlert, J. M.; Richichi, A.
Following up on our initial paper (Richichi and Ohlert, 2021), we report here on 60 lunar occultation events recorded between February 2021 and March 2024 at the Michael Adrian Observatorium. An improved version of the detector was employed for the present work. The program aims mainly at the direct measurement of the angular diameter of late-type…