Sensitivity of the Fermi Detectors to Gamma-Ray Bursts From Evaporating Primordial Black Holes (Pbhs)

Abstract

Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. The Fermi Gamma-ray Space Telescope observatory offers increased sensitivity to the gamma-ray bursts produced by PBHs with an initial mass of ∼ 5 × 10 14 g expiring today. PBHs are candidate progenitors of unidentified Gamma-Ray Bursts (GRBs) that lack X-ray afterglow. We propose spectral lag, which is the temporal delay between the high and low energy pulses, as an efficient method to identify PBH evaporation events with the Fermi Large Area Telescope (LAT).

Searching for Exploding black holes

“…(iii) PBH explosions must be local, i.e. within, at most, a few parsecs of Earth, to be detectable by current and planned facilities [12]; the evaporation process thus potentially (albeit not necessarily) exhibits proper motion, depending on the age, distance, and PBH direction of motion relative the line of sight;…”

What we cannot learn from analogue experiments

“…But, as lab experiments on tailored artificial micro black holes seem impossible at the moment, the only options are to look out for small black holes either in particle detection facilities (see e.g., Giddings & Thomas (2002) or Dimopoulos & Landsberg (2001) for proposals in this direction), or in the history of our universe. The Fermi-Gamma Ray Space Telescope (in a low-Earth orbit since 2008) has been searching, among other things, for radiative remnants of relatively small black hole objects from the beginning of the universe (see for instance, Ukwatta et al (2010)).…”