Normalization of autocorrelation function for multiple-tau photon correlator

A reduced symmetric normalization procedure was presented to reduce the requirement for hardware channels, which needs only one monitor channel in each linearity module. Theory analysis proves that the standard deviation of the reduced symmetric normalization approximates to that of the symmetric normalization and far smaller than that of the standard normalization at large delay time. Measurements with polystyrene particles of 90 nm, 1000 nm and 90 nm mixed with 1000 nm show superiority of both symmetric and reduced symmetric normalization over standard normalization. Calculated average standard deviation of standard normalization estimator is 2.5 to 3.5 times larger than that of the symmetric and reduced symmetric ones while the maximum deviation is 4.5 to 8.5 times. Reduced symmetric normalization achieves high statistical accuracy at the expense of obviously reduced additional monitor channels compared with symmetric normalization in multi-tau photon correlator.