SUB-PHOTOSPHERIC, RADIATION-MEDIATED SHOCKS IN GAMMA-RAY BURSTS: MULTIPLE SHOCK EMISSION AND THE BAND SPECTRUM

@article{Keren2014SUBPHOTOSPHERICRS,
  title={SUB-PHOTOSPHERIC, RADIATION-MEDIATED SHOCKS IN GAMMA-RAY BURSTS: MULTIPLE SHOCK EMISSION AND THE BAND SPECTRUM},
  author={Shai Keren and Amir Levinson},
  journal={The Astrophysical Journal},
  year={2014},
  volume={789}
}
We compute the time-integrated, thermal emission produced by a series of radiation-mediated shocks that emerge from the photosphere of a gamma-ray burst outflow. We show that for a sufficiently broad distribution of shock strengths, the overall shape of the time-integrated spectral energy distribution below the peak is a power law, νEν∝να, with a slope of 1 < α < 2. A substructure in the spectral energy distribution (SED) can also be produced in this model for certain choices of the shock train… 

Radiation-mediated Shocks in Gamma-Ray Bursts: Pair Creation

Relativistic sub-photospheric shocks are a possible mechanism for producing prompt gamma-ray burst (GRB) emission. Such shocks are mediated by scattering of radiation. We introduce a time-dependent,

Photospheric Emission in Gamma-Ray Bursts

A major breakthrough in our understanding of gamma-ray bursts (GRB) prompt emission physics occurred in the last few years, with the realization that a thermal component accompanies the over-all

Physics of Gamma-Ray Bursts Prompt Emission

In recent years, our understanding of gamma-ray bursts (GRB) prompt emission has been revolutionized, due to a combination of new instruments, new analysis methods, and novel ideas. In this review,

Monte Carlo simulations of relativistic radiation-mediated shocks: II. photon-starved regime

Radiation-mediated shocks (RMS) play a key role in shaping the early emission observed in many transients. In most cases, e.g. shock breakout in supernovae, llGRBs, and neutron star mergers, the

Signs of magnetic acceleration and multizone emission in GRB 080825C

One of the major results from the study of gamma-ray bursts with the Fermi Gamma-ray Space Telescope has been the confirmation that several emission components can be present in the energy spectrum.

HYDRODYNAMIC PROPERTIES OF GAMMA-RAY BURST OUTFLOWS DEDUCED FROM THE THERMAL COMPONENT

We study the properties of a significant thermal emission component that was identified in 47 gamma-ray bursts observed by different instruments. Within the framework of the “fireball” model, we

Electromagnetic Precursors of Short Gamma-Ray Bursts as Counterparts of Gravitational Waves

Precursor emissions are found in some short gamma-ray bursts (SGRBs). In this paper, we review the theories and observations of the SGRB precursor and discuss its prospect as an electromagnetic

UHECR acceleration at GRB internal shocks

We study the acceleration of cosmic-ray protons and nuclei at GRB internal shocks. Physical quantities (magnetic fields, baryon and photon densities, shock velocity) and their time evolution,

Particle acceleration, magnetization and radiation in relativistic shocks

What are the mechanisms of particle acceleration and radiation, as well as magnetic field build up and decay in relativistic shocks are open questions with important implications to various phenomena

References

SHOWING 1-10 OF 19 REFERENCES

OBSERVATIONAL SIGNATURES OF SUB-PHOTOSPHERIC RADIATION-MEDIATED SHOCKS IN THE PROMPT PHASE OF GAMMA-RAY BURSTS

A shock that forms below the photosphere of a gamma-ray burst (GRB) outflow is mediated by Compton scattering of radiation advected into the shock by the upstream fluid. The characteristic scale of

SUB-PHOTOSPHERIC EMISSION FROM RELATIVISTIC RADIATION MEDIATED SHOCKS IN GRBs

It is proposed that the prompt emission observed in bursts that exhibit a thermal component originates from relativistic radiation mediated shocks (RRMS) that form below the photosphere of the

VERY HIGH EFFICIENCY PHOTOSPHERIC EMISSION IN LONG-DURATION γ-RAY BURSTS

We numerically analyze the evolution of a long-duration gamma-ray burst jet as it leaves the progenitor star and propagates to the photospheric radius, where radiation can be released. We find that

QUASI-BLACKBODY COMPONENT AND RADIATIVE EFFICIENCY OF THE PROMPT EMISSION OF GAMMA-RAY BURSTS

We perform time-resolved spectroscopy on the prompt emission in gamma-ray bursts (GRBs) and identify a thermal, photospheric component peaking at a temperature of a few hundreds keV. This peak does

The Synchrotron Shock Model Confronts a “Line of Death” in the BATSE Gamma-Ray Burst Data

The synchrotron shock model (SSM) for gamma-ray burst emission makes a testable prediction: that the observed low-energy power-law photon number spectral index cannot exceed -2/3 (where the photon

A Compact Fireball Model of Gamma-Ray Bursts

It is proposed that the gamma-ray burst (GRB) 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

The Observable Effects of a Photospheric Component on GRB and XRF Prompt Emission Spectrum

A thermal radiative component is likely to accompany the first stages of the prompt emission of gamma-ray bursts (GRBs) and X-ray flashes (XRFs). We analyze the effect of such a component on the

On thermalization in gamma-ray burst jets and the peak energies of photospheric spectra

The low-energy spectral slopes of the prompt emission of most gamma-ray bursts (GRBs) are difficult to reconcile with radiatively efficient optically thin emission models irrespective of the

The peak energy of dissipative GRB photospheres

ABSTRACT The radiation released at the transparency radius of an ultrarelativistic flow can account forthe observed properties of gamma-ray bursts (GRBs) provided that sufficient energy is dissi-pated

FAST RADIATION MEDIATED SHOCKS AND SUPERNOVA SHOCK BREAKOUTS

We present a simple analytic model for the structure of non-relativistic and relativistic radiation mediated shocks. At shock velocities βs ≡ vs/c ≳ 0.1, the shock transition region is far from