Search Publications
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…
Dependence of star formation rate on different properties of molecular clouds
Mondal, Ashok; Chattopadhyay, Tanuka
Properties of molecular clouds (MCs) lying in our Galaxy and their star formation scenarios have been investigated with the help of multivariate unsupervised machine learning techniques concerning several observable parameters. At first, the MCs have been classified into four coherent groups using the standard K-means clustering method. Subsequent…
Analysis of photometric and spectroscopic variability of red supergiant Betelgeuse
Jadlovský, Daniel; Krtička, Jiří; Paunzen, Ernst +1 more
Betelgeuse is a pulsating red supergiant whose brightness is semi periodically variable and in February 2020 reached a historical minimum, the Great Dimming. The aims of this study are to characterize Betelgeuse's variability based on available archival data and to study possible causes of light variability. Many spectra, from ultraviolet and opti…
A constrained cosmological model in f(R ,Lm) gravity
Singh, J. K.; Shaily; Myrzakulov, Ratbay +1 more
In this article, we study the expanding nature of the universe in the context of f(R ,Lm) gravity theory, here R represents the Ricci scalar and Lm is the matter Lagrangian density. With a specific form of f(R ,Lm) , we obtain the field equations for flat FLRW metric. We parametrize the deceleration parameter in te…
DeGaPe 35: Amateur discovery of a new southern symbiotic star
Charbonnel, Stéphane; Garde, Olivier; Merc, Jaroslav +6 more
In this work, we present the discovery and characterization of a new southern S-type symbiotic star, DeGaPe 35. We have obtained the low-resolution spectroscopic observations and supplemented them with the photometry from Gaia DR3 and other surveys. The optical spectra of this target show prominent emission lines, including highly ionized [Fe VII]…