Left panel: broadband SED of Mrk 501 on MJD 56857.98 compiled using data from MAGIC (orange circles, corrected for EBL attenuation), Fermi-LAT (averaged over four and ten days, blue circles), Swift-XRT (red triangles), Swift-BAT (integrated flux in 14–195 keV from one-day observations, shown with green circles), Swift-UVOT (purple circles), KVA (purple square), and Metsähovi (pink square). The SSC+π⁰ model SED is overplotted (solid line). For comparison, we also show the SED when Bethe-Heitler pair production is neglected (dashed line), and the purely leptonic (SSC) model (dotted line). Right panel: zoom-in of the γ-ray spectrum.