Search Publications
Hints of point-symmetric structures in SN 1987A: The jittering jets explosion mechanism
Soker, Noam
I identify a point-symmetric structure composed of three pairs of clumps in the recently released JWST image of the ejecta of SN 1987A and argue that these pairs of clumps support the jittering jets explosion mechanism (JJEM) for SN 1987A. I compare this point-symmetric structure with the multipolar-lobe morphology of a post-asymptotic giant branc…
Exploring the cosmological model in f(R ,Tϕ) gravity with observational constraints
Bhardwaj, Vinod Kumar; Garg, Priyanka
We have investigated an isotropic and homogeneous cosmological model of the universe in f(R ,Tϕ) gravity, where Tϕ is the trace of the energy-momentum tensor and R is the Ricci scalar. We developed and presented exact solutions of field equations of the proposed model by taking the parametrization q(z) = α + βz/1 + z , where …
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…
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…
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…
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…
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…
A possible large-scale alignment of galaxy spin directions - Analysis of 10 datasets from SDSS, Pan-STARRS, and HST
Shamir, Lior
Multiple observations made by several different telescopes have shown asymmetry between the number of spiral galaxies rotating in opposite directions in different parts of the sky. One of the immediate questions regarding the possible asymmetry of the spin directions is whether the distribution forms a cosmological-scale axis. This paper analyzes …