A digital data acquisition system for the detectors at gammasphere

Abstract

A new data acquisition system for experiments using the Gammasphere detector array and associated detectors including the double-sided silicon strip detector (DSSD) is under development. Waveform digitization and triggering hardware identical to that developed for GRETINA has been procured and interfaced to the both the existing Gammasphere and DSSD detectors to provide significantly increased data throughput and increased event rates. A new parasitic signal connection and cable plant provides the ability to simultaneously measure the same events using both the old and new systems. A triggering interface module has been manufactured that connects the Gammasphere trigger and clock to the new system. A second digital data acquisition system has been attached to the DSSD detector located downstream from Gammasphere. The trigger systems of Gammasphere, Digital Gammasphere and Digital DSSD have successfully synchronized the clocks of all three data acquisition systems demonstrating timestamp correlation across multiple detector systems. New firmware for the digitizer modules specific to the signals provided by the Gammasphere detector has been developed and is currently being tested in situ to directly compare the energy resolution of the two data acquisition systems. We describe the system as implemented and show test results to date, where significantly faster event processing rates have been obtained with nearly equivalent energy resolution.