Galaxies, Volume 13, Issue 1

Observations of Very High Energy (VHE) gamma ray sources using the ground-based Imaging Atmospheric Cherenkov Telescopes (IACTs) play a pivotal role in understanding the non-thermal energetic phenomena and acceleration processes under extreme astroph...

We obtain universal relations for fluid spheres without rotation made of dark energy assuming the extended Chaplygin gas equation-of-state. After integrating the relevant differential equations, we make a fit to obtain the unknown coefficients of the...

Cooling down large test masses up to 200 kg, as foreseen for the Einstein Telescope, is a complex challenge combining cutting-edge technological achievements from different disciplines with the experience gained from both room-temperature and cryogen...

Quantum technology is central to the operation of modern gravitational-wave detectors and will play crucial role in the success of next-generation observatories, such as the Einstein Telescope. There, quantum squeezed light will be utilized to suppre...

The aim of the analysis of data from the Gaia Space Observatory is to obtain kinematic parameters of the collective motion of stars in a part of our galaxy. This research is based on a statistical analysis of the motion of $55,038,539$ stars selected i...

The Einstein Telescope (ET) will be a third-generation Gravitational Wave (GW) detector that will tackle cutting-edge technological challenges. The ET will be constructed at a depth of 200–300 m to isolate it from vibrations caused by seismic w...

The star $\gamma$ Cas and its analogs are a subset of Be stars that display particularly hard and bright thermal X-ray emission, which has no equivalent among other massive stars. Here, I will review their characteristics and present the latest result...

Gamma-ray bursts are known to display various features on top of their canonical behavior. In this short review, we will describe and discuss two of them: the ultra-long gamma-ray bursts, which are defined by an extreme duration of their prompt phase...

It has long been known that the observed mass surface density of cored dark matter (DM) halos is approximately constant, independently of the galaxy mass (i.e., ${\rho }_c{r}_c\simeq \mathrm{constant}$, with ${\rho }_c$ and $r_c$ being the central volume density and the radi...

The results of observations of the object Th4-4 in 1970–2024 showed that during this period the object went through several stages, when its characteristics corresponded to different classes of objects: Be star, symbiotic star and planetary neb...

We propose that modifications to the Higgs potential within a narrow atmospheric layer near the event horizon of an astrophysical black hole could significantly enhance the rate of sphaleron transitions, as well as transform the Chern–Simons nu...

So far, most of the about 5700 exoplanets have been discovered mainly with radial velocity and transit methods. These techniques are sensitive to planets in close orbits, not being able to probearge star–planet separations. μ-lensing is the...

I discuss here the progress made in the last decade on a few of the key open problems in GRB physics. These include (1) the nature of GRB progenitors, and the outliers found to the collapsar/merger scenarios; (2) jet structures, whose existence becam...

We compute the generalized spin precession frequency (${\Omega }_p$) of a test gyroscope in a stationary spacetime, specifically for a Kerr–MOG black hole within the framework of scalar–tensor–vector gravity (STVG), also known as modifie...