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Pinelli, D.

Publications and source records attributed to Pinelli, D..

Evaluation of radiation hardness of semiconductor materials against alpha particles for an API detector

An Associated Particle Imaging (API) system consists of a high vacuum chamber where deuterium ions are accelerated on a tritium-loaded target, resulting in alpha particles and neutrons emitted back-to-back, the latter escaping the chamber and used, for example, for tomography of a high-Z sample. An accurate determination of the alpha position is crucial to determine the trajectory of the neutron. Existing API systems have several limitations which a semiconductor-based API detector placed inside the vacuum chamber should not present. The semiconductor material can be either silicon or diamond. In particular, large and fast signals are generated by the alpha interactions in these materials. A pixelated API detector will measure the time and hit position of the alphas produced in the reaction. However, during the lifetime of the generator, the semiconductor detector will be exposed to an intense flux of alpha particles that will degrade its performance over time. To assess the radiation hardness of silicon and diamond against the alpha particles, we exposed single diodes made of either of the two materials to a 5 MeV alpha flux generated by an 241Am radioactive source. During irradiation, the diodes were biased and mounted on current-sensitive preamplifier boards. We have therefore been able to measure insitu the evolution of the waveforms as the damage was accumulating in their substrates.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Multi-Element Germanium Detectors with Integrated Readouts

In this study, we have developed a series of monolithic multi-element germanium detectors coupled with custom developed CMOS application specific integrated circuit (ASIC) for readout. Several strip detectors with element counts ranging from 64 to 384 were developed and are currently used at the National Synchrotron Light Source II in Brookhaven National Laboratory and the Advanced Photon Source in Argonne National Laboratory. Lastly, the detectors are photon counting and are used at high-energy diffraction and energy dispersive diffraction beamlines.

47 OTHER INSTRUMENTATION↗

Multi-element germanium detectors for synchrotron applications

In this paper, we have developed a series of monolithic multi-element germanium detectors, based on sensor arrays produced by the Forschungzentrum Julich, and on Application-specific integrated circuits (ASICs) developed at Brookhaven. Devices have been made with element counts ranging from 64 to 384. These detectors are being used at NSLS-II and APS for a range of diffraction experiments, both monochromatic and energy-dispersive. Compact and powerful readout systems have been developed, based on the new generation of FPGA system-on-chip devices, which provide closely coupled multi-core processors embedded in large gate arrays. Finally, we will discuss the technical details of the systems, and present some of the results from them.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗