Search for the Hawking radiation of primordial black holes: prospective sensitivity of LHAASO

Primordial black holes (PBHs) with initial mass 510^14 g are evaporating due to Hawking radiation, leading to bursts of very-high-energy gamma rays. In this work, we investigate the prospective sensitivity of the Large High Altitude Air Shower Observatory (LHAASO) to measure the local burst rate density of PBHs. Our findings reveal that LHAASO is capable of searching for the PBH bursts within a distance 0. 1 pc from the sun and thereby measure the local burst rate density 1164 (or 699) \, pc^-3\, yr^-1 at 99\% confidence level during a 3 (or 5) year observing run. This stands for a sensitivity that is one order of magnitude stronger than the strongest observational constraint from the High Altitude Water Cherenkov Observatory (HAWC). In addition, we further suggest an observing strategy to search for the PBH bursts during upcoming observing runs of LHAASO.