Related papers: Compton dragged gamma-ray bursts: the spectrum
We study in details how the pulse width of gamma-ray bursts is related with energy under the assumption that the sources concerned are in the stage of fireballs. Due to the Doppler effect of fireballs, there exists a power law relationship…
The recent progress in studies of gamma-ray bursts, their afterglows, and host galaxies is discussed. The emphasis is given to high-energy phenomena associated with gamma-ray burst explosions: high-energy cosmic rays, neutrinos,…
Recent results of the hectic research activity about gamma-ray bursts will be reviewed, with emphasis about the emission processes at the origin of the observed gamma-rays. The conventional synchrotron shock scenario is found to have…
Gamma-ray bursts (GRBs) and their early afterglows ionise their circumburst material. Only high-energy spectroscopy therefore, allows examination of the matter close to the burst itself. Soft X-ray absorption allows an estimate to be made…
An X-ray short burst associated with a Galactic fast radio burst was observed in 2020, distinguished by its X-ray cut-off energy significantly exceeding that of other X-ray short bursts. X-ray photons of these short bursts are believed to…
We consider the physics of neutrinos in a fireball, i.e. a tightly coupled plasma of photons, positrons and electrons. Such a fireball is believed to form in the first stages of a gamma-ray burst. We assume the fireball is…
Recent gamma-ray burst observations have revealed late-time, highly energetic events which deviate from the simplest expectations of the standard fireball picture. Instead they may indicate that the central engine is active or restarted at…
The extended lobes of radio galaxies are examined as sources of X-ray and gamma-ray emission via inverse Compton scattering of 3K background photons. The Compton spectra of two exemplary examples, Fornax A and Centaurus A, are estimated…
It is proposed that the gamma ray burst photons near the peak of the spectrum at several hundred KeV are produced on very compact scales, where photon production is limited by blackbody effects and/or the requirement of energetic quanta…
Previous studies of the evolution of gamma-ray burst spectra have generally relied on fitting sequences of spectra. These studies usually were confined to bright bursts and often lacked sufficient temporal resolution. We have developed…
A new calculation of the Galactic diffuse gamma-ray spectrum from the decay of secondary particles produced by interactions of cosmic-ray protons with interstellar matter is presented. The calculation utilizes the modern Monte Carlo event…
We propose a model for the spectral formation of Gamma Ray Burst (GRB) prompt emission, where the phenomenological Band's function is usually applied to describe the GRB prompt emission. We suggest that the GRB prompt emission is mainly a…
Stars twinkle to the eye through atmospheric turbulence, but planets, because of their larger angular size, do not. Similarly, scintillation due to the local interstellar medium will modulate the radio flux of gamma-ray-burst afterglows and…
Observations suggest that $\gamma$-ray bursts (GRBs) are produced by the dissipation of the kinetic energy of a relativistic fireball. We show that a large fraction, $\ge 10%$, of the fireball energy is expected to be converted by…
Air shower experiments have detected cosmic ray events of energies upto 300 EeV. Most likely these cosmic rays have originated from compact objects. Their exact sources are yet to be identified. It has been suggested before that gamma ray…
Observations of gamma-ray bursts by the Fermi satellite, capable of detecting photons in a very broad energy band: 8keV to >300GeV, have opened a new window for the study of these enigmatic explosions. It is widely assumed that photons of…
Clusters of galaxies are believed to be capable to accelerate protons at accretion shocks to energies exceeding 10^18 eV. At these energies, the losses caused by interactions of cosmic rays with photons of the Cosmic Microwave Background…
Understanding of the nature of gamma-ray bursts (GRBs) is one of the challenging problem facing the astrophysics community. The field of gamma ray bursts is a rapidly developing one and we expect that new missions, like SWIFT and GLAST will…
We calculate the flux of ultra high energy photons from individual ordinary (i.e. non-superconducting) cosmic strings and compare the results with the sensitivity of current and proposed TeV and EeV telescopes. Our calculations give only…
The X-ray background is generated by various classes of objects and variety of emission mechanisms. Relative contribution of individual components depends on energy. The goal is to assess the integral emission of the major components of the…