Digital Signal Emulator for the NAB Experiment

The goal of the Nab experiment is to measure the electron-neutrino decay correlation coefficient a to a precision of 10^-3 and also the Fierz interference term b to a precision of 3x10^-3 in neutron beta decay.  Our goal is 100 ps systematic timing precision and 2 keV energy resolution in each of the two 128-channel segmented silicon detectors.  The data acquisition system is based on waveform digitizers with custom digital pulse processing filters to enhance the efficiency of the low-threshold proton trigger.  In order to test the system independent of the detectors, we developed a digital signal emulator that generates pulses based on the input energy spectrum, pulse shape, and spectral noise density.  We will present our algorithm and test results of the data acquisition system and discuss further development possibilities.