Related papers: Detectability of Pair Echos from Gamma-Ray Bursts …
We discuss the possibility of observing ultra high energy cosmic ray sources inhigh energy gamma rays. Protons propagating away from their accelerators produce secondary electrons during interactions with cosmic microwave background…
We discuss the possible simultaneously UV/optical emission accompanying Gamma-ray bursts (GRBs). We show that as long as the intrinsic spectrum of GRB can extend to $\sim$10 GeV or higher, there is a large amount of relativistic $e^\pm$…
The injection of ultra-high energy cosmic rays in the intergalactic medium leads to the production of a GeV-TeV gamma-ray halo centered on the source location, through the production of a high electromagnetic component in the interactions…
In the framework of the internal shock scenario, we model the broadband prompt emission of gamma-ray bursts (GRBs) with emphasis on the GeV-TeV bands, utilizing Monte Carlo simulations that include various processes associated with…
Gamma-ray bursts (GRBs) are bright flashes of electromagnetic radiation originating from the core collapse of massive stars or the merger of compact objects. It has long been theorized that GRBs can emit very high-energy (VHE) gamma rays…
We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs,…
The mechanism responsible for the prompt emission of gamma-ray bursts (GRBs) is still a debated issue. The prompt phase-related GRB correlations can allow to discriminate among the most plausible theoretical models explaining this emission.…
Gamma Ray Bursts (GRBs) are among the most powerful sources in the Universe: they emit up to 10^54 erg in the hard X-ray band in few tens of seconds. The cosmological origin of GRBs has been confirmed by several spectroscopic measurements…
In the external shock model, gamma-ray burst (GRB) emissions are produced by the energization and deceleration of a thin relativistic blast wave due to its interactions with the circumburst medium (CBM). We study the physical properties of…
Gamma-ray bursts (GRBs) are the ultimate cosmic lighthouses, capable of illuminating the universe at its earliest epochs. Could such events probe the properties of the first stars at z $\sim$ 20, the end of the cosmic Dark Ages? Previous…
Gamma-ray bursts are cosmological sources emitting radiation from the gamma-rays to the radio band. Substantial observational efforts have been devoted to the study of GRBs during the prompt phase, i.e. the initial burst of high-energy…
We make a new estimate of the extragalactic radio background down to kHz frequencies based on the observed luminosity functions and radio spectra of normal galaxies and radio galaxies. We have constructed models for the spectra of these two…
The presence of delayed GeV emission after a strong transient, such as a GRB (Gamma-Ray Burst), in the VHE (Very-High Energy, $E>100$ GeV) band can be the signature of a non-zero magnetic field in the intergalactic medium. We used a…
The Fermi satellite has been reporting the detailed temporal properties of gamma-ray bursts (GRBs) in an extremely broad spectral range, 8 keV - 300 GeV, in particular, the unexpected delays of the GeV emission onsets behind the MeV…
Very-high-energy gamma rays produce electron positron pairs in interactions with low-energy photons of extragalactic background light during propagation through the intergalactic medium. The electron-positron pairs generate secondary gamma…
If gamma-ray bursts originate in dense stellar forming regions, the interstellar material can imprint detectable absorption features on the observed X-ray spectrum. Such features can be detected by existing and planned X-ray satellites, as…
Gamma-ray bursts (GRBs) were first detected thanks to their prompt emission, which was the only information available for decades. In 2010, while the high-energy prompt emission remains the main tool for the detection and the first…
Gamma-ray bursts (GRBs) are one of the main targets for the observations of the MAGIC telescopes. As a result of the effort in improving the sensitivity of the instrument and the automatic follow-up strategy, MAGIC detected two GRBs in the…
Gamma-ray bursts (GRBs) are a promising probe of the high-redshift Universe, but their detection remains observationally challenging. In this work, we explore the detectability of high-$z$ GRBs by the Wide-field X-ray Telescope (WXT) aboard…
It has recently been proposed that ultrahigh energy ($\gtrsim 10^{19}$ eV) cosmic rays (UHECRs) are accelerated by the blast waves associated with GRBs. We calculate the observed synchrotron radiation spectrum from protons and energetic…