LRTTM E_L-I type distribution functions of the non-thermal electron energies versus positions with a colour-coded M(μ₀) corresponding to V m^-1 and var(E_L) = 1 V m^-1 in the VAL C atmosphere at time t = 0.3 s after the beam injection into the loop at its apex. Left: M^FF; right: M^SU. The solid lines indicate the instantaneous energy deposits corresponding to ℱ₀/2 = 2.5 × 10⁹ erg cm^-2 s^-1, the dotted horizontal lines the bottom boundary of the magnetic mirror, the grey area the secondary re-acceleration region, and the blue ellipses labelled L and H denote tails in the particle distribution function. Only the vicinity of the footpoints is displayed.