Future constraints on primordial black holes from XGIS-THESEUS

Current observations allow primordial black holes (PBHs) in asteroid mass range 10(17)-10(22) g to constitute the entire dark matter energy density (barring a small mass range constrained by 21-cm observations). In this work, we explore the possibility of probing PBHs with masses 10(17)-10(19) g via the upcoming X/Gamma Ray Imaging Spectrometer (XGIS) telescope array on board the Transient HighEnergy Sky and Early Universe Surveyor (THESEUS) mission. While our projected limits are comparable with those proposed in the literature for 10(16) g < M-PBH < 10(17) g, we show that the XGIS-THESEUS mission can potentially provide the strongest bound for 10(17) g < M-PBH less than or similar to 3 x 10(18) g for nonrotating PBHs. The bounds become more stringent by nearly an order of magnitude for maximally rotating PBHs in the mass range 5 x 10(15) g < M-PBH 10(19) g.