2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/211578The time resolution of a double-stage Thick-GEM (THGEM) detector was measured with UV-photons and relativistic electrons. The photon detector, with semitransparent- or reflective-photocathode yielded time resolution of about 8-10ns RMS for single photoelectrons and 0.5-1ns RMS for few-hundred photoelectrons per photon-pulse. Time resolution of about 10ns RMS was recorded for relativistic electrons from a 106Ru source.8 Pages, 10 Figures, Submitted to JINSTInstrumentation and Detectorstext