Related papers: GRB990123: The Case for Saturated Comptonization
Swift triggered on a precursor to the main burst of GRB 061121 (z=1.314), allowing observations to be made from the optical to gamma-ray bands. Many other telescopes, including Konus-Wind, XMM-Newton, ROTSE and the Faulkes Telescope North,…
The complete high-resolution lightcurves of Swift GRB 080319B present an opportunity for detailed temporal analysis of the prompt optical emission. With a two-component distribution of initial Lorentz factors, we simulate the dynamical…
I calculate the emission expected from a Poynting-flux-dominated gamma-ray burst (GRB) flow in which energy is dissipated gradually by magnetic reconnection. In this picture, the energy of the radiating particles is determined by heating…
Models where relativistic jets from merger or accretion induced collapse in compact binary systems produce cosmological gamma ray bursts (GRBs) also predict that GRBs are accompanied by delayed emission of high energy photons, TeV…
We selected a sample of 33 Gamma Ray Bursts (GRBs) detected by Swift, with known redshift and optical extinction at the host frame. For these, we constructed the de-absorbed and K-corrected X-ray and optical rest frame light curves. These…
The observations of gamma-ray bursts (GRBs) such as 980425, 031203 and 060218, with luminosities much lower than those of other classic bursts, lead to the definition of a new class of GRBs -- low-luminosity GRBs. The nature of the outflow…
Gamma-ray bursts of short duration may harbor vital clues to the range of phenomena producing bursts. However, recent progress from the observation of optical counterparts has not benefitted the study of short bursts. We have searched for…
We present a multi-wavelength analysis of gamma-ray burst GRB 090727, for which optical emission was detected during the prompt gamma-ray emission by the 2-m autonomous robotic Liverpool Telescope and subsequently monitored for a further…
We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time-resolved photometry using optical data obtained by the TAROT telescope, using BAT…
For the first time, the consequences of combining two well-established empirical relations, describing different aspects of the spectral evolution of observed gamma-ray burst (GRB) pulses, are explored. These empirical relations are: i) the…
We present the time-resolved optical emission of GRB 060111B during its prompt phase, measured with the TAROT robotic observatory. This is the first time that the optical emission from a gamma-ray burst has been continuously monitored with…
Recent observational and theoretical studies have raised the possibility that the collimated outflows in gamma-ray burst (GRB) sources have two distinct components: a narrow (opening half-angle $\theta_{\rm n}$), highly relativistic…
The Swift burst GRB 110205A was a very bright burst visible in the Northern hemisphere. GRB 110205A was intrinsically long and very energetic and it occurred in a low-density interstellar medium environment, leading to delayed afterglow…
The synchrotron optical flash caught in GRB 990123 overlaps with the MeV radiation front, and the optical-emitting electrons must also produce GeV-TeV emission by inverse Compton scattering of MeV photons. The ultra-high-energy flash can be…
The origin of the prompt emission in gamma-ray bursts (GRBs) is still an unsolved problem and several different mechanisms have been suggested. Here we fit Fermi GRB data with a photospheric emission model which includes dissipation of the…
Simultaneous $\gamma$-ray measurements of gamma-ray burst (GRB) spectra and polarization offer a unique way to determine the underlying emission mechanism(s) in these objects as well as probing the particle acceleration mechanism(s) that…
Recent detections of kilonova-like emission following long-duration gamma-ray bursts GRB211211A and GRB230307A have been interpreted as originating from the merger of two neutron stars. In this work, we demonstrate that these observations…
We calculate the synchrotron self-Compton emission from internal shocks occurring in relativistic winds as a source of gamma-ray bursts, with allowance for self-absorption. For plausible model parameters most pulses within a Gamma-Ray Burst…
We present broadband multi-wavelength observations of GRB 080310 at redshift z = 2.43. This burst was bright and long-lived, and unusual in having extensive optical and near IR follow-up during the prompt phase. Using these data we attempt…
The dominant radiation mechanism that produces the prompt emission in gamma-ray bursts (GRBs) remains a major open question. Spectral information alone has proven insufficient in elucidating its nature. Time-resolved linear polarization has…