Gamma-Ray Burst detection prospects for next generation ground-based VHE facilities

Abstract

Gamma-ray Bursts (GRB) were discovered by satellite-based detectors as powerful sources of transient $\gamma$-ray emission. The Fermi satellite detected an increasing number of these events with its dedicated Gamma-ray Burst Monitor (GBM), some of which were associated with high energy photons $(E>10\mathrm{GeV})$, by the Large Area Telescope (LAT). More recently, follow-up observations by Cherenkov telescopes detected very high energy emission $(E>100\mathrm{GeV})$ from GRBs, opening up a new observational window with implications on the interpretation of their central engines and on the propagation of very energetic photons across the Universe. Here, we use the data published in the 2nd Fermi-LAT Gamma Ray Burst Catalogue to characterise the duration, luminosity, redshift and light curve of the high energy GRB emission. We extrapolate these properties to the very high energy domain, comparing the results with available observations and with the potential of future instruments. We use observed and simulated GRB populations to estimate the chances of detection with wide-field ground-based $\gamma$-ray instruments. Our analysis aims to evaluate the opportunities of the Southern Wide-field-of-view Gamma-ray Observatory (SWGO), to be installed in the Southern Hemisphere, to complement CTA. We show that a low-energy observing threshold $(E_{low}<200\mathrm{GeV})$, with good point source sensitivity $(F_{lim}\approx 10^{-11}\mathrm{erg}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$ in $1\mathrm{yr})$, are optimal requirements to work as a GRB trigger facility and to probe the burst spectral properties down to time scales as short as $10\mathrm{s}$, accessing a time domain that will not be available to IACT instruments.

10 pages, 4 figures, published on MNRAS

References in corpus (11)

• Multi-messenger Observations of a Binary Neutron Star Merger
• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Observations of the Crab Nebula with H.E.S.S
• Long gamma-ray bursts and core-collapse supernovae have different environments
• The 1% Concordance Hubble Constant
• Teraelectronvolt emission from the $\gamma$-ray burst GRB 190114C
• A very-high-energy component deep in the Gamma-ray Burst afterglow
• The major upgrade of the MAGIC telescopes, Part I: The hardware improvements and the commissioning of the system
• A decade of Gamma-Ray Bursts observed by $Fermi$-LAT: The 2${}^{nd}$ GRB catalog
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. VII. Properties of the Host Galaxy and Constraints on the Merger Timescale
• MAGIC observations of the nearby short gamma-ray burst GRB 160821B