arXiv subjects

Donald Pinelli

Publications and source records attributed to Donald Pinelli.

3 recordsLinked to original sources

arXiv2025

A Virtual Frisch-Grid Geometry-Based CZT Gamma Detector for In-Field Radioisotope Identification

We present a Virtual Frisch-Grid geometry-based CZT gamma detector developed for identifying different radioisotopes over an energy range from single keV up to 2 MeV, and useful for efficient characterization of CZT crystals. The detector is built with a 3 x 3 matrix of CZT crystals, each measuring approximately 6 mm x 6 mm x 15 mm. The charge generated within the sensor's active volume is read out via an anode connected directly to the AVG3_Dev integrated circuit. A current signal induced by charge drift is collected on side pads of the crystals, enabling reconstruction of a 3D interaction position. This paper discusses the design, development, and performance of the standalone, mobile detector system, which integrates the AVG3_Dev readout IC developed at Brookhaven National Laboratory, high-speed FPGA-based with per-channel digital signal processing, and embedded system capabilities. The device is compact, battery-powered, and supports wireless data streaming, making it suitable for field operations towards radioisotope identification.

physics.ins-det↗

arXiv2025

Evaluation of a Full Field Fluorescence Imager with Synchrotron Radiation

The design and evaluation on the NSLS-II beamline of the 3FI application specific integrated circuit (ASIC) bump-bonded to a simply, planar, two-dimensionally segmented silicon sensor is presented. The ASIC was developed for Full-Field Fluorescence spectral X-ray Imaging (3FI). It is a small-scale prototype that features a square array of 32x32 pixels with a pitch of 100 {\mu}m. The ASIC was implemented in a 65 nm CMOS process. Each pixel incorporates a charge-sensitive amplifier, shaping filter, discriminator, peak detector, and sample-and-hold circuit, allowing detection of events and storing signal amplitudes. The system operates in an event-driven readout mode, outputting analog values for threshold-triggered events, allowing high-speed multi-element X-ray fluorescence imaging. At power consumption of 200 {\mu}W per pixel, consisting almost uniquely of power dissipated in analog blocks, 308 eV full width at half maximum (FWHM) energy resolution at 8.04 keV, that corresponds to 30 e- rms equivalent noise charge (ENC) and 138 eV FWHM energy resolution at 3.69 keV (16 e- rms ENC) were obtained, for Cu and Ca K{\alpha} lines, respectively. Each pixel operates independently, and the detector enables in situ trace element microanalysis in biological and environmental research. Its architecture addresses limitations of X-ray Fluorescence Microscopy (XFM), typically requiring mechanical scanning, by offering frame-lees data acquisition, translating to high-throughput operation. The 3FI ASIC is suitable for example for studies of nutrient cycling in the (mycor)rhizosphere, microbial redox processes, and genotype-phenotype correlations in bio-energy crops. Additional performances, such as enhanced spatial resolution can be further improved with coded-aperture and Wolt, extending the use to environmental, biomedical, and material science studies.

physics.ins-det↗

arXiv2018

Multi-element Germanium Detectors for Synchrotron Applications

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. We will discuss the technical details of the systems, and present some of the results from them.

physics.ins-det↗