The prompt X-ray (0.4–2 keV) light curve of EP260321a. The EP-WXT and EP-FXT data are taken from W. Yuan et al. (2026). The curves are the model light curves from MC simulations: MC 1 (green), δr = 4 × 10¹² cm, and τ_m = 1.5; MC 2 (blue), δr = 2 × 10¹² cm, and τ_m = 2; MC 3 (red), δr = 1.5 × 10¹² cm, and τ_m = 3. See the text for the other parameters in the MC simulation.