高能天体物理现象

Long gamma-ray burst (GRB) prompt emission shows a correlation between the intrinsic peak energy, $E_{\mathrm{p,i}}$, of the time-average $\nu F_{\nu}$ spectrum and the isotropic-equivalent peak gamma-ray luminosity, $L_{{\rm p,iso}}$, as…

In this work, we focus on the study of radiation induced desorption processes that occurred in acetonitrile ice irradiated by broadband X-rays (6 eV to 2 keV) monitored by FTIR spectroscopy at different radiation fluences. In a previous…

Double-bump showers are a rare class of extensive air showers (EAS) predicted by Monte Carlo simulations. They occur when a high-energy secondary particle, the leading particle, travels significantly farther than the rest, creating a…

We present the first XRISM/Resolve observation of the persistently accreting neutron star (NS) low-mass X-ray binary Serpens X-1. The source was observed on October 17th, 2024, for approximately 350 ks of elapsed time, resulting in 171 ks…

The sustained gamma ray emission (SGRE) from the Sun is one of the fascinating high energy phenomena closely related to the acceleration of protons to energies >300 MeV. Here we report on the solar cycle variation of SGRE events based on…

The structural evolution of rotating protoneutron stars encodes essential information about their observable signatures, while microscopic properties provide complementary knowledge to advance observational investigations. Using a…

We present a detailed analysis of the Type-I (thermonuclear) X-ray bursts and eclipses observed from the neutron star low-mass X-ray binary (LMXB) EXO 0748--676 with AstroSat during the second known outburst of the source following a…

We show that the parameters used to standardize the luminosity of Type 1a supernovae in the SALT2 and SiFTO models are strongly dependent on the redshift z. Consequently, when standardized with increasing z, the average absolute magnitudes…

A significant fraction of gravitational-wave mergers are expected to be eccentric in the Laser-Interferometer-Space-Antenna (LISA) frequency band, $10^{-4} - 10^{-1}$ Hz. Several LIGO-Virgo-KAGRA events show potential hints of residual…

The interaction of cosmic rays (CRs) with magnetic fields and the interstelar medium (ISM) leads to the production of nonthermal radiation. Although this has been a topic of study for many years, it still poses many challenges to the…

Mean motion resonances (MMRs) are a generic outcome of convergent migration for bodies embedded in accretion disks around a central mass. Long studied in planetary systems, the same phenomenon should occur for stellar-mass black holes (BHs)…

We present a unified theoretical framework for induced (stimulated) scattering-parametric instabilities of electromagnetic waves, including induced Compton, stimulated Brillouin, and stimulated Raman scattering (SRS) in strongly magnetized…

White dwarfs (WDs) can be used as laboratories to test strong gravity and high-density regimes, once their equation of state is not so uncertain as the one of neutron stars. This makes them also a useful tool to constrain dark-matter…

Neutron star high-mass X-ray binaries are well-studied in wavebands between the infrared and hard X-rays. Their low-frequency millimeter and radio properties, on the other hand, remain poorly understood. We present observations of the…

A new SPHERE seires complex extensive air showers detector is under development. The main goal of its mission is to study the mass composition of cosmic ray nuclei in the 1-100 PeV energy range at a new level. The already well-established…

Gravitational waves (GWs) from coalescing binary black holes (BBHs) can come from different environments. GWs interact gravitationally with astrophysical objects, which makes it possible to use gravitational lensing by objects in the same…

At the dawn of the gamma-ray burst (GRB) afterglow era, a Cepheid-like correlation was discovered between time variability V and isotropic-equivalent peak luminosity Liso of the prompt emission of about a dozen long GRBs with measured…

Many X-ray binaries are transiently accreting. Having statistics on their recurrence times is helpful to address questions related to binary evolution and populations, as well as the physics of binary systems. We compile a catalog of known…

Symbiotic stars are binary systems where a white dwarf (WD) accretes material from the wind of an evolved, late-type companion. X-ray-emitting symbiotic systems are classified into $\alpha$, $\beta$, $\delta$, and $\beta/\delta$ types,…

We present JWST/NIRSpec and NIRCam observations of the first optically selected off-nuclear tidal disruption event (TDE), AT 2024tvd, along with Keck/KCWI integral field unit spectroscopy. The spectra show broad H and He emission lines that…