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In PET detector designs, high sensitivity is a critical performance parameter required for obtaining images with reasonable signal-to-noise ratio (SNR). The sensitivity of a PET scanner is primarily determined by the efficiency of detection system (e.g. crystal thickness and solid angle coverage), but could be enhanced by distinguishing and recovering inter-crystal Compton scattering events while...
Breast density evaluation is an active topic in the breast imaging field. This can be accurately measured separating fibroglandular tissue from adipose tissue using material decomposition techniques. In this work, we present a Bayesian approach, based on a Poisson maximum likelihood material decomposition method and that includes an adjustable prior, known from the compressed breast thickness during...
FARCOS (Femtoscope ARray for Correlation and Spectroscopy) is a novel modular detection system featuring high angular and energy resolution. It aims at reconstructing the particle's momentum at high precision and performing correlation measurements of LCPs and of LCPs and IMFs. The final system will be composed of 20 telescopes and the first prototypes will be ready to take data starting from 2017...
High-Voltage CMOS (HVCMOS) pixel sensors are depleted active pixel sensors implemented in standard commercial CMOS processes. Thanks to its radiation hardness and fast signal generation HVCMOS pixel sensors will be used, or are proposed, for several experiments: Mu3e [2], ATLAS [3], CLIC [4]. In 2015, the first reticle size HVCMOS sensor has been fabricated on high resistive substrates as a part of...
KLOE-2 at the e+e− DAφNE φ-factory is the main experiment of the INFN Frascati National Laboratories (LNF) and is the first high-energy experiment using the GEM technology with a cylindrical geometry, a novel idea that was developed at LNF exploiting the kapton properties to build a light and compact tracking system. Four concentric cylindrical triple-GEM detectors, for a total material budget below...
A first prototype of a readout ASIC in CMOS 65 nm for a pixel detector at High Luminosity LHC is described. The pixel cell area is 50×50 μm2 and the matrix consists of 64×64 pixels. The chip was designed to guarantee high efficiency at extreme data rates for very low signals and with low power consumption. Two different analogue front-end designs, one synchronous and one asynchronous, were implemented,...
With the aim of improving the CNR of the LabPET II scanner, a method to correct the channel-to-channel coincidence time difference has been developed. The LabPET II, an avalanche photodiode-based PET scanner, features up to 55 000 channels which benefit from precise timing alignment. The correction process is fully automated and embedded in the scanner hardware and firmware. It uses a timing probe...
A new method using a stopped cosmic-ray beam for the calibration of an electro-magnetic calorimeter which consists of several hundreds of modules has been established. Cosmic muons stop in the calorimeter, and positrons (and electrons) from the muon decays with the maximum energy of 53 MeV are used for the energy calibration. These events could be identified as double pulses observed by a flash ADC...
Radiation imaging systems provide a wealth of information for analyzing quantities of interest (enumeration, strength, dimensions) of an uncharacterized source. This capability is useful, for example, when measuring plutonium powder “held up” in unknown locations at reprocessing facilities. Accurate models of the imager are required to infer the quantity of interest. This paper describes the modeling...
In compact systems, precise measurement in the projection space may be compromised due to minification. The objective of this work is to investigate the impact of the magnification factor in a model-based calibration procedure. This has direct relevance to the geometrical calibration of the clinical INSERT camera. Projection data from three point sources were simulated for a single pinhole collimator...
The SuperKEKB collider at KEK, which has started its commissioning with beam in February 2016, is designed to achieve unprecedented luminosities, with a factor 40 higher than the record-breaking luminosity of the KEKB machine. For the operation of the Belle II detector, in particular of its pixel vertex detector, a precise understanding of the background conditions at the interaction point of the...
In this work we compare different calibration sources and focus on their combination to optimize the calibration of large-format X-ray imagers over a wide range. This activity is carried out in the framework of the DSSC project and the primary aim is the calibration of the DSSC camera. We considered pulsed IR laser, radioactive sources, X-ray tube, electrical injection devices, X-ray synchrotron beam,...
The European X-ray Free Electron Laser (XFEL.EU) is currently being commissioned in Schenefeld, Germany. From 2017 onwards it will provide spatially coherent X-rays of energies between 0.25 keV and 25keV with a unique timing structure. One of the detectors foreseen at XFEL.EU for the soft X-ray regime (energies below 6keV) is a quasi column-parallel readout FastCCD developed by Lawrence Berkeley National...
Photon counting X-ray detectors with energy discrimination capabilities can discriminate the energy of incident X-ray photon, thereby spectral imaging is possible with them. Energy calibration is a process to find a linear mapping function between the amplitudes of electric pulses and their corresponding photon energy. For practical and efficient energy calibration, the X-ray tube voltage can be used...
In the context of the development of a simultaneous SPECT/MRI system, we have previously proposed a multi-mini-slit-slat (MSS) collimator, with multiple sections of short slits in order to improve the angular sampling. The data can be reconstructed using a 3D reconstruction algorithm that models the collimator geometry. One drawback, however, is that the projection data obtained with this collimator...
The CALICE Collaboration [1] is developing highly granular calorimeters for a future e+e− linear collider. The development of the calorimeters is driven by the Particle Flow approach (PFA) in order to achieve a jet energy resolution of 3–4% [2]. The Analog Hadronic Calorimeter (AHCAL) is one of the detector concepts based on 30×30×3 mm3 scintillating tiles read out by Silicon Photomultipliers (SiPM)...
The Intensity Modulated Radiotherapy allows a more efficient dose delivery in the tumour leading to a reduction of the dose deposited in the nearby healthy organs. However, this technique requires additional resources to perform on line dosimetry and insure patient safety. A quasi transparent 2D transmission detector for monitoring the treatment X-ray beam has been developed. It includes a high performance...
We present an RF amplitude detector with a conversion gain of −3 V/V for RF amplitude range 0 to 0.6 Vp in 65nm CMOS. On-chip self-calibration structure that automatically corrects the variations within the RF detector itself is proposed. Silicon measurement results show the self-calibration structure improves the detection error of the non-calibrated RF amplitude detector to less than 10% at only...
A mixed-mode adaptive duty-cycle corrector loop (DCC loop) architecture with background calibration method is proposed. The duty-cycle correction range is 20%–80% with maximum 5.9ps duty error at 8GHz. The entire blocks of the DCC loop consume 4.1mA from 0.95 V supply voltage at 5GHz frequency. Successful operations of duty-cycle correction loop for various PVT conditions are verified via intensive...
This work presents focal plane modules for Radiation Budget Instrument, a passive remote-sensing instrument that follows the legacy of Clouds and Earth's Radiant Energy system to measure short and longwave Earth's radiation budget. The focal plane arrays are micromachined at JPL and integrated into sub-assembly modules to be mounted on the optical telescope of the instrument.
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