Universe, Volume 11, Issue 12

We investigate the long-term magnetic variability of OP And, a magnetically active single K giant, between 1993 and 2025. To track magnetic activity, we analyze the variability of the Hα line and two lines of the calcium infrared triplet. The v...

The Galactic X-ray transient EXO 1846-031 was first discovered during an outburst in 1985 by the EXOSAT mission. The source remained in a quiescent state for nearly 34 years after the first outburst. The source started its second outburst on 23 July...

Gamma-ray bursts (GRBs) are widely recognized to exhibit jet-like emission structures, though previous studies often assumed isotropic emission due to observational constraints. This assumption limited our understanding of the intrinsic properties of...

Flavor-changing neutral current (FCNC) processes play a prominent role in the search for physics beyond the Standard Model (SM) due to their sensitivity to new physics at the TeV scale. Meson–antimeson transitions and rare meson decays provide...

An analysis of the solar differential rotation (DR) during solar cycle No. 24 (SC24) (2009–2019), based on the Kanzelhöhe Observatory for Solar and Environmental Research (KSO) data set, is presented. The white-light images were processed...

This work investigates the evaporation of black holes immersed in a de Sitter environment, using the Vaidya-de Sitter spacetime. The role of cosmological observers is highlighted in the development and Hayward thermodynamics for non-stationary geomet...

In this work, we investigate the (pre)-inflationary dynamics of a flat, homogeneous, and isotropic universe governed by the Starobinsky potential within the framework of noncommutative effective loop quantum cosmology. The field equations are solved...

Radio-loud high-redshift quasars (RHRQs) provide crucial insights into the evolution of relativistic jets and their connection to the growth of supermassive black holes. Beyond the extensively studied population at z≥5, the cosmic morning epoch (3...

We investigate the nonrelativistic quantum dynamics of a spinless particle in a screw-type spacetime endowed with two independent twist controls that interpolate between a pure screw dislocation and a homogeneous twist. From the induced spatial metri...

In this paper we study the properties of Kasner cosmological solutions in Lovelock gravity. Recent progress in the investigation of flat cosmological models in Lovelock gravity unveiled the fact that in quadratic (Gauss–Bonnet) and cubic Lovelo...