# Astroparticle Physics - A Joint TeVPA/ IDM Conference

Jun 23 – 28, 2014
Amsterdam
Europe/Zurich timezone

## Observations of gamma-ray bursts with the HAWC observatory

Jun 23, 2014, 5:40 PM
15m
Room 2 (Tuschinski Theatre)

### Room 2

#### Tuschinski Theatre

Presentation Gamma-Ray Astrophysics

### Speaker

Dirk Lennarz (Georgia Tech)

### Description

The temporal evolution and end of GRB spectra have important implications for the acceleration mechanisms of gamma-ray bursts (GRBs). Above $\approx10$ GeV the effective area of \emph{Fermi}-LAT is approximately constant and since the photon flux is steeply decreasing with energy, an insufficient number of photons is detected. The High Altitude Water Cherenkov (HAWC) observatory is a gamma-ray detector in the 100 GeV - 100 TeV range currently under construction in central Mexico that has the potential to measure GRB spectra beyond the LAT energy range. Unlike Imaging Atmospheric Cherenkov Telescopes, it has a large field of view and near 100 % duty cycle that will allow for observations of the prompt GRB phase. In this presentation I will show first results of GRB observations with the partially completed HAWC array, including GRB 130427A, the most energetic GRB so far detected at a redshift $z<0.5$.

### Primary author

Dirk Lennarz (Georgia Tech)

### Co-author

HAWC collaboration for the (HAWC collaboration)

 Slides