Constant fraction timing with scintillation detectors

A model is presented for constant-fraction pick-off timing with scintillator-photomultiplier detectors based on a statistical method for leading-edge timing. Many of the essential features of this technique are obtained including prompt response, the dependence of full width at half maximum (FWHM) on the dynamic range of pulse heights and on the maximum energy deposited in the scintillator, and the effect of delay time on the optimum resolution in CFPHT (constant fraction of pulse height trigger) and ARC (amplitude-risetime compensation) timing. The `walk´ component in this technique is also satisfactorily reproduced