An efficient method for timing synchronization between many digital sampling channels

Future nuclear physics experiments are expected to rely more and more on fast digital sampling and digital signal processing methods, for energy, pulse-shape, and timing measurements. A common issue in these applications is the electronic synchronization between the various channels, i.e. the capability of performing timing coincidences or time-of-flight measurements. In this paper an efficient synchronization method is proposed, based on sampling a periodic reference signal with the same digitizer used for the detector signal. A fast digital signal processing algorithm to extract the relevant information from the data is presented and discussed. Calculations and experimental tests show that timing synchronization resolutions of the order of 10–100 ps FWHM are achievable, using standard fast sampling ADCs. The method can be easily applied to experiments having many channels and possibly different ADC sampling rates, thus overcoming one of the major drawbacks of the time-stamped clock approaches.