高能天体物理现象

A tight correlation between nuclear millimeter (mm) and X-ray emission has recently been found in nearby ($z < 0.01$) and low-Eddington ratio ($\rm \lambda_{Edd} < 0.1$) radio-quiet (RQ) Active Galactic Nuclei (AGN), suggesting a common…

When a rapidly-rotating, highly magnetized white dwarf (WD) approaches the Chandrashekhar limit through mass accretion, it can undergo an accretion-induced collapse (AIC) to form a proto-neutron star or protomagnetar. The protomagnetar can…

Modern particle-in-cell (PIC) codes have become an integral tool in plasma astrophysics. As most plasma phenomena grow from initially small instabilities, it is important to ensure PIC codes can suppress noise and ensure that any growing…

Systematic errors in the parameter estimation (PE) of gravitational wave (GW) mergers can arise from various sources, including waveform systematics, noise mischaracterization, data analysis artifacts, and other unknown factors. In this…

The merger between the carbon (C) and oxygen (O) shells hours to days before the collapse of a massive star significantly changes its nucleosynthesis, which is reflected in the elemental ratios observed in supernova remnants (SNRs). We…

In isolated binary evolution, binary black hole (BBH) mergers are generally formed through stable mass transfer (SMT) or common envelope evolution. In recent years, the SMT channel has received significant attention due to detailed binary…

This work investigates the origin of the TeV emission detected by the Large High Altitude Air Shower Observatory (LHAASO) from NGC~4278, a galaxy hosting a low-luminosity active galactic nucleus (LLAGN). Considering two plausible scenarios,…

Very High Energy (VHE) gamma-rays in pulsars, and their surrounding halos, are interpreted to originate from the leptonic channel, electromagnetic interactions through electron inverse Compton (IC) scattering. In the hadronic scenario,…

In this work, we investigate synchrotron emission and the observational signatures of anisotropic non-thermal electrons during magnetic-flux eruptions in a magnetically arrested disk, using 3D GRMHD simulations. Non-thermal electrons are…

The rate of observed gravitational waves (GWs) from neutron star-neutron star (NS-NS) mergers detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) indicates the existence of more than one short gamma-ray bursts (sGRBs)…

The high redshift merger rate and mass distribution of black hole binaries provide a direct probe to distinguish astrophysical black holes (ABHs) and primordial black holes (PBHs), which can be studied using the Stochastic…

Explosive nucleosynthesis is affected by many uncertainties, particularly regarding assumptions and prescriptions adopted during the evolution of the star. Moreover, simple explosion models are often used in the literature, which can…

We investigate neutrino signatures of a hadron-quark phase transition (HQPT) in neutron stars (NS) leading to quark star (QS) formation. We use representative hadronic and quark equations of state i.e. DD2 and MIT bag model along with a…

The equation of state (EOS) of cold dense matter is a central open problem in nuclear astrophysics. Its inference is hindered by the lack of \textit{ab initio} control above about twice nuclear saturation density, requiring extrapolation.…

The potential to detect axion dark matter through astrophysical processes has shown high promise in recent years. We therefore expand on previous work studying the axion-to-photon conversion efficacy of neutron stars and the interstellar…

This chapter tells the still-unfolding story of extracting polarization signatures from general relativistic magnetohydrodynamics simulations of accretion disks. In some sense, this effort is premature as there are still very few results of…

We report the discovery of a new candidate pulsating ultraluminous X-ray source (PULX) in NGC 5128 (Centaurus A). The candidate, 4XMM J132542.2-425943, is a transient source, identifiable as a clear X-ray point source for $\sim 8$ months in…

Context. The spatially coherent multipath propagation of pulsar radiation leads to a temporal and spectral interference patterns called scintillation. It is caused by density variations in the ionized interstellar medium, which often take…

Radio waves propagating through the interstellar medium are influenced by variations in plasma density. For spatially localised plasma structures along the line of sight, time-delay Doppler analyses of pulsars often reveal scintillation…

The spectrum and composition of ultra-high-energy cosmic rays (UHECRs) suggest that the population dominating above the ankle releases particles with an unusual hard spectrum at low rigidity, below the EV scale. In self-confinement…