A 32-channel 12-bit ADC-32ATC analog-to-digital conversion module with signal shape digitization at 40 MHz, which was been developed for the VES experiment at the U-70 accelerator, is presented. The analog shapers for this module, the measurement methods, the data-processing techniques, and the experience gained in using this module in the VES experiment are described. The module is intended to register single pulses with a stable shape or a linear combination of a few such pulses with positive coefficients. It can be used for calorimeters, as well as for Cherenkov and scintillation counters, in fixed-target experiments in high-energy physics.
A complex of the new electromagnetic calorimeter (ECAL-2) for the VES setup is described. It is composed of 1592 “shashlik” type counters consisting of a set of lead−scintillator plates, high-voltage supplies based on cascade voltage multipliers for FEU-84 photomultiplier tubes, an LED-based monitoring system, a slow control system, and a pulse-height analysis system. The procedures of ECAL-2 calibration and online monitoring are described.
Preliminary results obtained by studying K − π −, K − π − π 0, and K − π − η systems in the VES experiment are presented. No statistically significant signals from possible resonances were observed in two- and three-particle mass spectra of doubly charged (sub)systems.