Performance of the NA62 LAV front-end electronics

The NA62 experiment [1] will measure the BR(K+→π+ν) to within about 10%. To reject the dominant background from final state photons, the large-angle vetoes (LAVs) must detect particles with better than 1 ns time resolution and 10% energy resolution over a very large energy range. A low threshold, large dynamic range, Time-over-threshold based solution has been developed for the LAV front end electronics. Our custom 32 channel 9U board uses a pair of low threshold discriminators for each channel to produce LVDS logic signals. The achieved time resolution obtained in laboratory, coupled to an HPTDC based readout board, is ~ 150 ps.