Abstract
Afterglows of gamma-ray bursts are observed to produce light curves
with the flux following power law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days.
One proposed explanation for these flares is the interaction of a relativistic
blast wave with a circumburst density transition. In this paper, we model
this type of interaction computationally in one and two dimensions, using
a relativistic hydrodynamics code with adaptive mesh refinement called
ram, and analytically in one dimension. We simulate a blast wave traveling
in a stellar wind environment that encounters a sudden change in
density, followed by a homogeneous medium, and compute the observed
radiation using a synchrotron model. We show that flares are not observable
for an encounter with a sudden density increase, such as a wind
termination shock, nor for an encounter with a sudden density decrease.
Furthermore, by extending our analysis to two dimensions, we are able to
resolve the spreading, collimation, and edge effects of the blast wave as it
encounters the change in circumburst medium. In all cases considered in
this paper, we find that a flare will not be observed for any of the density
changes studied.
with the flux following power law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days.
One proposed explanation for these flares is the interaction of a relativistic
blast wave with a circumburst density transition. In this paper, we model
this type of interaction computationally in one and two dimensions, using
a relativistic hydrodynamics code with adaptive mesh refinement called
ram, and analytically in one dimension. We simulate a blast wave traveling
in a stellar wind environment that encounters a sudden change in
density, followed by a homogeneous medium, and compute the observed
radiation using a synchrotron model. We show that flares are not observable
for an encounter with a sudden density increase, such as a wind
termination shock, nor for an encounter with a sudden density decrease.
Furthermore, by extending our analysis to two dimensions, we are able to
resolve the spreading, collimation, and edge effects of the blast wave as it
encounters the change in circumburst medium. In all cases considered in
this paper, we find that a flare will not be observed for any of the density
changes studied.
| Original language | English |
|---|---|
| Publication status | Published - 1 Aug 2013 |
| Event | 7th Huntsville Gamma-Ray Burst Symposium, GRB 2013 - Nashville, Tennessee, USA United States Duration: 14 Apr 2013 → 18 Apr 2013 |
Other
| Other | 7th Huntsville Gamma-Ray Burst Symposium, GRB 2013 |
|---|---|
| Country/Territory | USA United States |
| City | Tennessee |
| Period | 14/04/13 → 18/04/13 |
Bibliographical note
Paper 26 in eConf Proceedings C1304143Keywords
- Astrophysics - High Energy Astrophysical Phenomena