Detection Probability of Single Photons and LIV Constraints in Gamma-Ray Astrophysics. Top: Probability of detecting at least a single photon with energy around E_min, P_Emin^1γ. The magenta band lines show the result for the Dominguez EBL model as well as its upper and lower limits. The solid blue line shows the energy measured by LHAASO at E = 18 TeV, and the blue band shows the energy region within 1 sigma of the energy resolution of the experiment (18 TeV ± 40%). Bottom: P_Emin^1γ with E_min = 18 TeV as a function of the LIV energy scale. The magenta band again represents the EBL uncertainty. The blue shaded areas represent the phase space of E_LIV rejected with a 2, 3, and 5σ confidence level by the most competitive LIV limits coming from gamma-ray astrophysics.