Time-integrated neutron-decay proton energy spectra at various positions s along the field line for a flare and a field line footpoint located on the equator (θ_f = 0° and θ_B = 0°). Panel (a) is for a footpoint longitude of ϕ_B = 45°, and panel (b) is for ϕ_B = 10°. The gray band identifies the 30–100 keV energy range.