Galaxies, Volume 11, Issue 2

We study radial oscillations in non-rotating neutron stars by considering the unified equation of states (EoSs), which support the 2 M_⊙ star criterion. We solve the Sturm–Liouville problem to compute the 20 lowest radial oscillation modes...

We review the recent theoretical and observational developments concerning the interaction of the Large Magellanic Cloud (LMC) with the Milky Way and its neighbourhood. An emerging picture is that the LMC is a fairly massive companion (10–20% o...

In this work, a perturbed system of the restricted three-body problem is derived when the perturbation forces are conservative alongside the corresponding mean motion of two primaries bodies. Thus, we have proved that the first and second types of pe...

In this paper, we investigate a scalar field cosmological model of accelerating Universe with the simplest parametrization of the equation of state parameter of the scalar field. We use $H\left(z\right)$ data, pantheon compilation of SN Ia data and BAO data to co...

The convective envelopes of solar-type stars and the convective cores of intermediate- and high-mass stars share boundaries with stable radiative zones. Through a host of processes we collectively refer to as “convective boundary mixing”...

The Kepler and TESS space missions significantly expanded our knowledge of what types of stars display flaring activity by recording a vast amount of super-flares from solar-like stars, as well as detecting flares from hotter stars of A-F spectral ty...

This review has two parts. The first one is devoted to the Barbier–Chalonge–Divan (BCD) spectrophotometric system, also known as the Paris spectral classification system. Although the BCD system has been applied and is still used for all...

We study radio and X-ray emissions from intermediate-mass black holes (IMBHs) and explore the unified model for accretion and ejection processes. The radio band survey of IMBH (candidate) hosted galaxies indicates that only a small fraction (∼0.6...

The optical and UV properties of radio-quiet (RQ) and radio-loud (RL, relativistically “jetted”) active galactic nuclei (AGN) are known to differ markedly; however, it is still unclear what is due to a sample selection and what is associa...

The Fanaroff–Riley Class II radio galaxy Cygnus A hosts jets that produce radio emission, X-ray cavities, cocoon shocks, and X-ray hotspots, where the jet interacts with the ICM. Surrounding one hotspot is a peculiar “hole” feature,...

If baryosynthesis is strongly nonhomogeneous, macroscopic regions with antibaryon excess can be created in the same process from which the baryonic matter is originated. This exotic possibility can become real, if the hints to the existence of antihe...

We present here the East Asia to Italy Nearly Global VLBI (EATING VLBI) project. How this project started and the evolution of the international collaboration between Korean, Japanese, and Italian researchers to study compact sources with VLBI observ...

The era of multi-messenger astronomy has recently be inaugurated with pioneering experiments, theoretical interpretation, and models [...]

Radio activity in AGN (Active Galactic Nuclei) produce feedback on the host galaxy via the impact of the relativistic jets on the circumnuclear gas. Although radio jets can reach up to several times the optical radius of the host galaxy, in this revi...

In this work, we studied the Galactic Center supermassive black hole (SMBH), Sagittarius A* (Sgr A${}^{*}$), with the KVN and VERA Array (KaVA)/East Asian VLBI Network (EAVN) monitoring observations. Especially in 13 May 2019, Sgr A${}^{*}$ experienced an unpreced...

We simulate the evolution of relativistic electrons injected into the intracluster medium by five radio galaxies. We study the spatial transport and the emission properties of the injected radio plasma over a ∼5 Gyr period, and the sequence of co...

The dynamical interaction between binary systems is crucial in understanding the nature of orbital motion under the influence of gravitational potential. In our study, we focused on investigating the effects of dynamical forces on the regularity of b...

Recently, a series of high-precision measurements by various experiments show that cosmic ray nuclei spectra begin to harden at ∼200 GV and the boron-to-carbon (B/C) ratio has a similar trend around the same energy. These anomalous structures pos...

Observational studies of GHz peaked spectrum (GPS) sources contribute to the understanding of the radiative properties and interstellar environment of host galaxies. We present the results from the multi-frequency high-resolution VLBI observations of...

We numerically study the origin of the multi-armed spiral structure observed in the circumnuclear gaseous mini-disks of nearby galaxies. We show that the presence of dust in such disks and its interaction with the gravitationally stable gaseous compo...

Magnetism is a ubiquitous property of astrophysical plasmas, yet stellar magnetism still remains far from being completely understood. In this review, we describe recent observational and modelling efforts and progress to expand our knowledge of the...

Obtaining high-resolution images at centimeter-or-longer wavelengths is vital for understanding the physics of jets. We reconstructed images from the M87 22 GHz data observed with the East Asian VLBI Network (EAVN) by using the regularized maximum li...

In the past few years, the Event Horizon Telescope (EHT) has provided the first-ever event horizon-scale images of the supermassive black holes (BHs) M87${}^{*}$ and Sagittarius A${}^{*}$ (Sgr A${}^{*}$). The next-generation EHT project is an extension of the EHT array t...