(a) PSP observations of the energetic particles from EPI-Lo, EPI-Hi/LET + HET, the magnetic-field variation, and the radio emission by FIELDS (Bale et al. 2016) before and during the Labor Day event on 2022 September 5. Three vertical lines, from left to right, mark the flare eruption time, SEP event onset time (Cohen et al. 2024), and the shock arrival time, respectively. (b) Relative positions of PSP and Solar Orbiter to the flare region during the event (Gieseler et al. 2023). The Parker spiral lines were calculated using the averaged solar-wind velocities measured at PSP before the start of the SEP events.