Relaxation times measurement in single and multiply excited xenon clusters

Direct measurement of the rates of nonradiative relaxation processes in electronically excited xenon clusters were carried out. The clusters were created in a pulsed supersonic beam and twophoton excited by femtosecond laser pulses with a wavelength of 263 nm. The measurements were performed using the pump-probe method and electron spectroscopy. It is shown thatrelaxation of light clusters XeN (N < 15) predominantly occurs by desorption of excited xenon atoms with a characteristic time constant of 3 ps. Heavier electronically excited clusters (N> 10) vibrationally relax to the lowest electronically excited state at a rate of about 0.075 eV / ps. Multiply excited clusters are deactivated via energy exchange between excited centers with theionization of one of them. The production of electrons in this process occurs with a delay of ~ 4 ps from the pump pulse, and the process is completed in 10 ps.