Time-of-flight analysis of thermionic emission produced by intense femtosecond laser excitation of silver

Construction and performance details of a chevron microchannel plate (MCP) based time-of-flight (TOF) spectrometer utilizing a pulsed laser source are presented as well as an analysis of MCP range and linearity relevant to obtaining quantitative information from measured electron yields. We present experimental TOF distributions of electrons thermionically emitted from Ag(111) exposed to intense 100 femtosecond optical pulses. Spectra resulting from variable delay pump-probe pulses reveal a nonequilibrium electron population at several 10{dollar}sp5 sp{lcub}rm o{rcub}{dollar}K which cools in 200 fs.