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Total Data Readout (TDR) is a powerful data acquisition tool developed for use with Recoil Decay Tagging (RDT) experiments on the GREAT (Gamma, Recoil, Electron, Alpha Tagging) spectrometer. RDT experiments correlate prompt radioactive decays detected at the target position with subsequent decays of recoiling reaction products implanted in GREAT, located at the focal plane of the RITU recoil separator, several microseconds later. TDR uses independent channels associated in a software event builder based on timestamps to form a single time ordered data stream. It is crucial to maintain the accuracy of the timestamps over long periods (microseconds to hours) for the study of Exotic Nuclei. The TDR system cannot be tested fully by use of calibrated sources with GREAT and a novel method of verifying the system is required. Our solution is to use the predictable randomness of a Pseudo Random Number generator based on Linear Feedback Shift Registers (LFSR) implemented in a 16 channel VME module. The random value defines the delay between pulses into the TDR system. The recorded results are sorted and checked for correspondence with the LFSR sequence. We show the method, design of the module, and discuss the results and benefits of the tests

AGATA is a 4-pi array of high purity Ge detectors for in-beam gamma-ray spectroscopy based on the novel concepts of pulse shape analysis (PSA) and gamma-ray tracking. Tracking and PSA require the concurrent digitization-at a sampling rate of 100 Msamples/s-of preamplifier signals of the 36-fold segmented Ge crystals composing the array. Locally digitized data are optically transferred to remote pre-processing nodes for pulse energy computation. The design of the front-end readout and level-1 (L1) trigger in AGATA follows a synchronous pipeline model: the detector data are stored in pipeline buffers at the global AGATA frequency, waiting the global L1 decision. A global timing system provides a reference clock and time tag to the digitizers and the pre-processing units by means of a tree of optically connected timing units. Pre-processing nodes are integrated in advanced TCA-based carrier cards with full mesh connectivity in the backplane and read-out through pci-express based optical links. The front-end data readout and its integration in the global trigger and synchronization system will be described.

A single-width D-sized VXI card has been designed and built to fully instrument one of the new Clover detectors designed for experiments with the EUROGAM array. Each Clover detector consists of four individual germanium (Ge) crystals and an escape suppression shield comprising 16 bismuth germanate (BGO) crystals. The Clover electronics card measures energy and timing data to 13-bit accuracy from each Ge crystal for spectroscopy and measures sum energy and timing for the BGO shield. It also records a complete Ge and BGO hit pattern for each event and performs intelligent hardware escape suppression to exploit the segmented nature of the Clover detectors.

EUROGAM was designed for gamma ray spectroscopy and the simplest mechanism for event detection is to count the number of coincident gamma rays detected in the array which gives a figure of merit to each event. The EUROGAM detector array uses the XIV backplane system for front-end electronics including triggering and readout. The main tasks of the trigger system are described. The trigger system is distributed with an intelligent local trigger in each of the detector electronics channels. Novel aspects of the system are the use of XIV lines to generate and to distribute trigger signals and the distributed nature of the system to allow efficient parallel and pipelined operation with low system dead times. Throughout the design of the trigger system the various design proposals were tested against a few difficult triggers devised by the physicists who intend to use the system. As an example, one of the simpler triggers is considered. >

A four channel VME card with 14 bit, 80 MHz digitizers and powerful on-board processing has been designed, built and used in tests of digital pulse processing techniques for gamma-ray tracking. This paper explains the background (rationale for the project), describes the VME card (known as the GRT4) and presents a 64 channel GRT4 digitizing system which was used to instrument two segmented Germanium detectors during in-beam tests. Results obtained using the GRT4 card are presented as well as some applications.