1,721,172 research outputs found
VME-Based Data Acquisition System for High-Resolution Position-Sensing Silicon Drift Detectors
No full textRome, Ital
A novel scatter detector based on the Controlled-Drift mechanism suitable for Compton prostate imaging
No full textImpact of Detector Parameters on Light Charged Particle and Intermediate Mass Fragments Identification through Pulse-Shape Analysis
No full textThe aim of this work is the study of the impact of the real preamplifier-detector configuration (i.e. finite bandwidth, input noise, leakage current, detector capacitance) on the measurement techniques used for fragment identification in charge and mass in multi-detector arrays for intermediate energy nuclear physics experiments. We refer to rise-time vs. energy diagram that allows charge identification and ToF techniques used for the identification of mass. In this work we derived a first model able to predict the detection system performance and useful to tailor both the detector and the front-end specifications to the specific experimental case. The requirements for the optimization result to be partly conflicting ToF technique requires fast timing signals, while pulse-shape analysis benefits from slower detector pulses
Multi-channel Acquisition System for High-Resolution Position-Sensing Silicon Drift Detectors
No full textWe present the design guidelines and the experimental characterization of a multichannel acquisition system that measures the amplitude and the time-of-arrival of the signal pulses delivered by position-sensing silicon drift detectors (SDDs).
The readout system has been equally developed for multichannel SDDs and for controlled drift detectors (CDDs) intended for spectroscopic imaging of X-rays or charged particles. The analog section includes a very large scale integration (VLSI) front-end preamplifier and bias current generator for the on-chip JFET follower while the digital back-end is realized with 12 bit 100 MS/s 8-channel analog-to-digital converter (ADC) versa modular eurocard
(VME) boards. Amplitude and time are measured by digitally processing each unipolar shaped pulse also in presence of a superposed background waveform. The VME modularity allows the expansion of the readout system up to 128 channels per VME crate. The overall linearity error is better than 0.05%, and the mean noise over all channels, expressed in terms of
equivalent noise charge, is about 4 electrons r.m.s. The measured time resolution is 0.6 ns r.m.s. at a signal charge of 5000 electrons, corresponding to a position resolution of 2–3 μm r.m.s. along the drift direction. The developed readout system has been used for X-ray imaging tests with CDDs at Sincrotrone Trieste
Semiconductor drift detectors for high resolution X-ray spectroscopy
No full textThe properties and performances of silicon driftdetectors for X-rayspectroscopy applications are presented. The peculiar characteristic of these detectors is the transport along the detector of the charge generated by the radiation toward a small collecting anode, whose capacitance can be as low as 60 fF, irrespective of the sensitive area. This feature is the key of the extremely highresolution available from this class of devices. Recent experimental results showing an energy resolution at room temperature down to 110 electrons rms with a detector of 1 cm2 active area and external electronics are reported. Detectors with different topologies especially designed to improve the resolution in the X-ray energy range are presented. The status of the activity on direct integration of the electronics in the detector itself is also reported
A novel scatter detector based on the Controlled-Drift mechanism suitable for Compton prostate imaging
No full textSimulation of the 3-D Coulomb Explosion of the Electron-Hole Distribution at High Injection Levels in 2-D Semiconductor Detectors
No full textWe developed a novel simulation code for 3-D electron-hole transport and signal formation in semiconductor detectors. The code includes thermal diffusion and Coulomb interaction between the carriers - essential for the correct simulation of high-density ionization tracks. The present work focuses on dedicated numerical techniques to correctly simulate the explosion of high-density charge carrier clouds down to the first instants of the time evolution, when extremely high field intensities are reached due to Coulomb interaction between carriers. The case study of a p+nn+ diode irradiated by 1 keV photons on under different bias and charge injection conditions up to 107 e.h pairs is presented and discussed. This case well represents the operating conditions foreseen in the imaging detectors for the novel FEL X-ray facilities and the potential of the developed simulation code
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