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 (DM) energy density (barring a small constrained by 21 cm observations). In this work, we explore possibility of probing PBH with masses $10^{17}-10^{19}\,{\rm g}$ via upcoming X and Gamma Imaging Spectrometer (XGIS) telescope array on-board Transient High-Energy Sky Early Universe Surveyor (THESEUS) mission. While our projected limits are comparable those proposed literature for $10^{16}\,{\rm g}\,<\,M_{\mathrm{PBH}}\,<\,10^{17}\,{\rm g}$, show that XGIS-THESEUS mission can potentially provide strongest bound $10^{17} \mathrm{~g}<M_{\mathrm{PBH}} \lesssim 3\times 10^{18} \mathrm{~g}$ non-rotating PBHs. The bounds become more stringent nearly an order magnitude maximally rotating PBHs $5\times10^{15}\,{\rm g}\,<\,M_{\rm PBH}\,\lesssim\,10^{19}\,{\rm g}$.