Distribution dn/dE of beam electrons over energy E at the four separate distances s (with a separate panel for each distance) indicated in Fig. 4, both for a simulation that ignores (solid green curve) and includes (dashed purple curve) magnetic gradient forces. Also included is the collisional rate of energy loss for a single electron, −(dE/dt)_coll, from Eq. (48) (solid grey curve). Summing a distribution curve and energy loss rate curve would yield a log-space curve of the integrand for the deposited power density Q_beam (Eq. (47)).