Triangular fitting to the rapid-rise, rapid-decay peak of the temporal profiles of electron fluxes a) and ion (carbon and heavier) count rates b) observed at 1 AU, for event #4. The temporal profiles at different energies have been shifted to achieve good separations. The black curves show the observations and the red curves are the best fits. The blue dots with uncertainties on the left or right of the panels represent the typical intensity of the pre-event background and of the peak with statistical errors. c) The error analysis for the 0.92 keV electron channel and the 1.67 MeV/nucleon ion channel. The green and blue curves are the upper and lower limits of fitting (that represent a 95% confidence interval), respectively. The limits on the start time of the corresponding injection are shown as error bars in Fig. 3a.