Time-correlated single photon counting for estimating duration of Na and continuum flashes in multibubble sonoluminescence spectra

Time-correlated single photon counting (TCSPC) using software was applied for estimating a duration and a sequence of the flashes of Na and continuum during multibubble sonoluminescence from aqueous NaCl and SDS solutions under 20 kHz ultrasound. The duration of Na flashes was defined as 5.1 ns, 8.0 ns, 11.7 ns for 5 M NaCl, 0.5 M NaCl, 5 mM SDS solutions, respectively. The duration of continuum flashes was varying as 2.1–2.9 ns for all solutions. The observed strong correlation between Na and continuum pulses shows that a bubble giving the both kinds of the flashes emits them simultaneously with a measured delay of about 0.5 ns for Na flash.