Search

Signal digitizers revolutionized the approach to the electronics readout of radiation detectors in Nuclear Physics. These highly specialized pieces of equipment are designed to acquire the signals that are characteristic of the detectors in nuclear physics experiments. The functions of the several modules that were once needed for signal acquisition, can now be substituted by a single digitizer. As suggested by the name, with such readout modules, signals are first digitized (i.e. the signal waveform is sampled and converted to a digital representation) and then either stored or analyzed on-the-fly. The performances can be comparable or better than the traditional analog counterparts, in terms of energy, time resolution, and acquisition rate. In this work, we investigate the use of general-purpose digital oscilloscopes as signal digitizers for nuclear detectors. In order to have a proper comparison, we employ a distributed data acquisition system (DAQ), that standardizes the interface between the hardware and the on-line data analysis. The signals, from a set of typical radiation detectors, are digitized and analyzed with the very same algorithms in order to avoid biases due to different software analysis. We compare two traditional signal digitizers (CAEN DT5725 and CAEN DT5751) to two low-cost digital oscilloscopes (Digilent Analog Discovery 2, and Red Pitaya STEMLab 125-14), in terms of their capabilities for spectroscopy (energy resolution), time resolution, pulse shape discrimination, and maximum acquisition rate., Comment: 17 pages, 8 figures, 4 tables, Prepared for submission to JINST

The Heavy Flavor Tracker (HFT) is a recently installed micro-vertex detector upgrade to the STAR experiment at RHIC, consisting of three subsystems with various technologies of silicon sensors arranged in 4 concentric cylinders. The two innermost layers of the HFT close to the beam pipe, the Pixel ("PXL") subsystem, employ CMOS Monolithic Active Pixel Sensor (MAPS) technology that integrate the sensor, front-end electronics, and zero-suppression circuitry in one silicon die. This paper presents selected characteristics of the PXL detector part of the HFT and the hardware, firmware and software associated with the readout system for this detector.