Optimization of parameters in photon counting experiments

Abstract

The effects of photomultiplier voltage, discriminator setting, and temperature on the signal-to-noise ratio in a photon counting experiment have been measured for several photomultiplier types. The photomultipliers tested were an RCA 1P28A, an RCA 4832, an RCA 1P21, and a Hamamatsu R406.The results Indicate that photon counting experiments should be performed at the hlghest possible photomultlpller voltage. The data also show that the increase in the signal-to-ndse ratio realized when the photomultiplier is cooled is very dependent on the photomultiplier type.

Photometric instrument with automatic switching between photon counting and analog modes

“…Measurement of the signal to noise ratio as a function of the discriminator voltage yielded results similar to those obtained by Niemczyk (13). The expected dependence of SNR on /V1''2 (where N is the observed number of PC counts) was observed at all Vd settings above approximately 40 mV.…”

“…Recently, several papers have focused on improved systems for photon counters (10,11), characteristics of photon counting systems (12), and optimal strategies for photon counting (13,14). The principal disadvantage of PC is the loss of linearity due to pulse pileup at high photon arrival rates (typically [105][106] Hz).…”

Determination of amino acids at subfemtomole levels by high-performance liquid chromatography with laser-induced fluorescence detection

“…Voltage and temperature settings of the PMT and the amplifier-discriminator threshold voltage were chosen by using the procedure of Niemcyk et al (20). The optimum values for the three parameters were as follows: PMT voltage, -1650 V dc; temperature, -16.3 °C; discriminator threshold voltage, 1.25 mV.…”

Application of time-correlated single photon counting and stroboscopic detection methods with an evanescent-wave fibre-optic sensor for fluorescence-lifetime-based pH measurements

“…A Hamamatsu H5773-20 PMT detector, optimized for photon counting, was used for all TCSPC measurements. The optimum discriminator value for the TCSPC module was determined using a procedure given in the literature [31] with the PMT gain set to approximately 80% full scale. Absorptive neutral density filters were used to maintain a count rate of one photon for 20 or more excitation pulses in order to meet Poisson criteria for photon counting and to minimize photon pile-up effects.…”