982 research outputs found

    A Low-Cost Unified Experimental FPGA Board for Cryptography Applications

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    This paper describes the evaluation of available experimental boards, the comparison of their supported set of experiments and other aspects. The second part of this evaluation is focused on the design process of the PCB (Printed Circuit Board) for an FPGA (Field Programmable Gate Array) based cryptography environment suitable for evaluating the latest trends in the IC (Integrated Circuit) security like Side–Channel Attacks (SCA) or Physically Unclonable Function (PUF). It leads to many criteria affecting the design process and also the suitability for evaluating and measuring results of the attacks and their countermeasures. The developed system should be open, versatile and unrestricted by the U.S. law [1]

    ProtoEXIST: Advanced Prototype CZT Coded Aperture Telescopes for EXIST

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    {\it ProtoEXIST1} is a pathfinder for the {\it EXIST-HET}, a coded aperture hard X-ray telescope with a 4.5 m2^2 CZT detector plane a 90×\times70 degree field of view to be flown as the primary instrument on the {\it EXIST} mission and is intended to monitor the full sky every 3 h in an effort to locate GRBs and other high energy transients. {\it ProtoEXIST1} consists of a 256 cm2^2 tiled CZT detector plane containing 4096 pixels composed of an 8×\times8 array of individual 1.95 cm ×\times 1.95 cm ×\times 0.5 cm CZT detector modules each with a 8 ×\times 8 pixilated anode configured as a coded aperture telescope with a fully coded 10∘×10∘10^\circ\times10^\circ field of view employing passive side shielding and an active CsI anti-coincidence rear shield, recently completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009. During the duration of its 6 hour flight on-board calibration of the detector plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along with the simultaneous measurement of the background spectrum and an observation of Cygnus X-1. Here we recount the events of the flight and report on the detector performance in a near space environment. We also briefly discuss {\it ProtoEXIST2}: the next stage of detector development which employs the {\it NuSTAR} ASIC enabling finer (32×\times32) anode pixilation. When completed {\it ProtoEXIST2} will consist of a 256 cm2^2 tiled array and be flown simultaneously with the ProtoEXIST1 telescope

    A double-sided silicon micro-strip super-module for the ATLAS inner detector upgrade in the high-luminosity LHC

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    The ATLAS experiment is a general purpose detector aiming to fully exploit the discovery potential of the Large Hadron Collider (LHC) at CERN. It is foreseen that after several years of successful data-taking, the LHC physics programme will be extended in the so-called High-Luminosity LHC, where the instantaneous luminosity will be increased up to 5 × 1034 cm−2 s−1. For ATLAS, an upgrade scenario will imply the complete replacement of its internal tracker, as the existing detector will not provide the required performance due to the cumulated radiation damage and the increase in the detector occupancy. The current baseline layout for the new ATLAS tracker is an all-silicon-based detector, with pixel sensors in the inner layers and silicon micro-strip detectors at intermediate and outer radii. The super-module is an integration concept proposed for the strip region of the future ATLAS tracker, where double-sided stereo silicon micro-strip modules are assembled into a low-mass local support structure. An electrical super-module prototype for eight double-sided strip modules has been constructed. The aim is to exercise the multi-module readout chain and to investigate the noise performance of such a system. In this paper, the main components of the current super-module prototype are described and its electrical performance is presented in detail

    The ARIEL Instrument Control Unit design for the M4 Mission Selection Review of the ESA's Cosmic Vision Program

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    The Atmospheric Remote-sensing Infrared Exoplanet Large-survey mission (ARIEL) is one of the three present candidates for the ESA M4 (the fourth medium mission) launch opportunity. The proposed Payload will perform a large unbiased spectroscopic survey from space concerning the nature of exoplanets atmospheres and their interiors to determine the key factors affecting the formation and evolution of planetary systems. ARIEL will observe a large number (>500) of warm and hot transiting gas giants, Neptunes and super-Earths around a wide range of host star types, targeting planets hotter than 600 K to take advantage of their well-mixed atmospheres. It will exploit primary and secondary transits spectroscopy in the 1.2-8 um spectral range and broad-band photometry in the optical and Near IR (NIR). The main instrument of the ARIEL Payload is the IR Spectrometer (AIRS) providing low-resolution spectroscopy in two IR channels: Channel 0 (CH0) for the 1.95-3.90 um band and Channel 1 (CH1) for the 3.90-7.80 um range. It is located at the intermediate focal plane of the telescope and common optical system and it hosts two IR sensors and two cold front-end electronics (CFEE) for detectors readout, a well defined process calibrated for the selected target brightness and driven by the Payload's Instrument Control Unit (ICU).Comment: Experimental Astronomy, Special Issue on ARIEL, (2017

    AttĂ©nuation des interactions Ă©lectromagnĂ©tiques entre le module de dĂ©tection LabPET II et l’IRM

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    Les scanners TEP/IRM simultanĂ©s offrent une occassion unique d'examiner en mĂȘme temps les propriĂ©tĂ©s anatomiques et fonctionnelles des tissus malins, tout en Ă©vitant l'incertitude des systĂšmes sĂ©quentiels de TEP/IRM. Cependant, le couplage Ă©lectromagnĂ©tique entre les deux modalitĂ©s constitue un dĂ©fi important Ă  relever. Ces interfĂ©rences Ă©lectromagnĂ©tiques entravent les performances du scanner et altĂšrent la qualitĂ© d'image de chaque modalitĂ©. Bien que les mĂ©taux possĂšdent d'excellentes propriĂ©tĂ©s de blindage contre les frĂ©quences radioĂ©lectriques, ils ne constituent pas nĂ©cessairement une option de blindage appropriĂ©e pour modifier les champs magnĂ©tiques induisant des courants de Foucault dans les couches mĂ©talliques. En consĂ©quence, il existe une demande considĂ©rable pour un nouveau matĂ©riau de protection et une approche originale pour retirer les piĂšces mĂ©talliques du champ de vision IRM. L’objectif de ce projet Ă©tait d’initier les Ă©tudes en vue de la rĂ©alisation d’un scanner TEP/IRM simultanĂ© basĂ© sur des modules de dĂ©tection LabPET II hautement pixĂ©lisĂ©s afin d’obtenir une rĂ©solution spatiale millimĂ©trique pour le cerveau humain et le chien. L'Ă©lectronique LabPET II comprend des circuits intĂ©grĂ©s Ă  application spĂ©cifique dans lesquels le signal est numĂ©risĂ© Ă  proximitĂ© de la photodiode Ă  avalanche et offre un environnement moins sensible aux interfĂ©rences Ă©lectromagnĂ©tiques. Pour atteindre l'objectif principal, premiĂšrement, l'effet du matĂ©riau mĂ©tallique des modules de dĂ©tection LabPET II sur les performances de la TEP et de l'IRM est examinĂ© thĂ©oriquement. Les rĂ©sultats confirment que les composants mĂ©talliques du module de dĂ©tection LabPET II altĂšrent le champ magnĂ©tique, gĂ©nĂšrent des courants de Foucault ce qui augmente leur tempĂ©rature. Ensuite, les performances Ă©lectroniques des modules de dĂ©tection LabPET II sous l’influence de bobines d’IRM faites sur mesure sont examinĂ©es. La rĂ©solution en Ă©nergie et la rĂ©solution temporelle se dĂ©tĂ©riorent en prĂ©sence de bobines RF et de bobines Ă  gradient en raison des perturbations Ă©lectromagnĂ©tiques. SubsĂ©quemment, un module de dĂ©tection LabPET II blindĂ© par une fine couche de composite cuivre-argent est Ă©tudiĂ©, prouvant que le blindage contre les interfĂ©rences Ă©lectromagnĂ©tiques avec le composite rĂ©tablit les performances en TEP, fournissant moins d'induction par courants de Foucault. En outre, une nouvelle configuration de blindage basĂ©e sur un composite de couche flexible de nanotubes de carbone a Ă©tĂ© fabriquĂ©e pour limiter les interfĂ©rences Ă©lectromagnĂ©tiques. Les composites de nanotubes de carbone crĂ©ent une couche hautement conductrice avec des chemins conducteurs minimaux, ce qui permet de rĂ©duire les courants de Foucault. Le principal rĂ©sultat scientifique de ce projet est que le blindage composite empĂȘche les interfĂ©rences de basses et hautes frĂ©quences et rĂ©duit l'induction de courants de Foucault, offrant ainsi la flexibilitĂ© nĂ©cessaire pour acquĂ©rir une sĂ©quence rapide de commutation de gradients. D'un point de vue technique, le module de dĂ©tection LabPET II ainsi blindĂ© prĂ©sente une excellente performance dans un environnement de type IRM, ce qui permet de concevoir un insert TEP basĂ© sur la technologie LabPET II.Abstract: Simultaneous PET/ MRI scanners provide a unique opportunity to investigate anatomical and functional properties of malignant tissues at the same time while avoiding the uncertainty of a sequential PET/MRI systems. However, electromagnetic coupling between the two modalities is a significant challenge that needs to be addressed. These electromagnetic interferences (EMI) hinder the performance of both scanners and distort the image quality of each modality. Although metals have excellent radio-frequency shielding properties, they are not necessarily an appropriate shielding option for altering magnetic fields that induce eddy currents in any metallic layer. Thus, there is a considerable demand for a new shielding material and an original approach to remove metallic parts from the MRI field of view. The objective of this project was to initiate the realization of a simultaneous PET/MRI scanner based on highly pixelated LabPET II detection modules to achieve millimeter spatial resolution for the human brain and dogs. The LabPET II electronics include application specific integrated circuits where the signal is digitized near the avalanche photodiode and offers an environment less susceptible to EMI. To fulfill the main aim, for the first time, the effect of the metallic material of LabPET II on PET and MRI performance was theoretically examined. Results confirm that metallic components of the LabPET II detection modules distort the magnetic field, generate eddy currents, and increase temperature. Then, the LabPET II electronics performance under the influence of custom-made MRI coils was investigated. Its energy and timing resolutions deteriorate in the presence of both RF and gradient signals because of EMIs. Thus, a LabPET II detection module shielded by a thin layer of the copper-silver composite was investigated, proving that shielding EMIs with the composite restores the PET performance, with less eddy current induction. Besides, a new shielding configuration based on a flexible layer of carbon nanotube (CNT) composite was fabricated to limit the EMIs. The CNT composite creates a highly conductive layer with minimal conductive paths that allows eddy currents to be decreased. The primary scientific outcome of this project is that the novel composite shielding rejects both low and high-frequency interferences and reduces eddy current induction, offering the flexibility to acquire a fast gradient switching sequence. From a technical point of view, the shielded LabPET II detection module demonstrates an excellent performance in an MRI-like environment supporting the feasibility of designing a PET-insert based on LabPET II technology

    Design and construction of a Cherenkov imager for charge measurement of nuclear cosmic rays

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    A proximity focusing Cherenkov imager called CHERCAM, has been built for the charge measurement of nuclear cosmic rays with the CREAM instrument. It consists of a silica aerogel radiator plane across from a detector plane equipped with 1,600 1" diameter photomultipliers. The two planes are separated by a ring expansion gap. The Cherenkov light yield is proportional to the charge squared of the incident particle. The expected relative light collection accuracy is in the few percents range. It leads to an expected single element separation over the range of nuclear charge Z of main interest 1 < Z < 26. CHERCAM is designed to fly with the CREAM balloon experiment. The design of the instrument and the implemented technical solutions allowing its safe operation in high altitude conditions (radiations, low pressure, cold) are presented.Comment: 24 pages, 19 figure

    The ABC130 barrel module prototyping programme for the ATLAS strip tracker

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    For the Phase-II Upgrade of the ATLAS Detector, its Inner Detector, consisting of silicon pixel, silicon strip and transition radiation sub-detectors, will be replaced with an all new 100 % silicon tracker, composed of a pixel tracker at inner radii and a strip tracker at outer radii. The future ATLAS strip tracker will include 11,000 silicon sensor modules in the central region (barrel) and 7,000 modules in the forward region (end-caps), which are foreseen to be constructed over a period of 3.5 years. The construction of each module consists of a series of assembly and quality control steps, which were engineered to be identical for all production sites. In order to develop the tooling and procedures for assembly and testing of these modules, two series of major prototyping programs were conducted: an early program using readout chips designed using a 250 nm fabrication process (ABCN-25) and a subsequent program using a follow-up chip set made using 130 nm processing (ABC130 and HCC130 chips). This second generation of readout chips was used for an extensive prototyping program that produced around 100 barrel-type modules and contributed significantly to the development of the final module layout. This paper gives an overview of the components used in ABC130 barrel modules, their assembly procedure and findings resulting from their tests.Comment: 82 pages, 66 figure
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