Search results for "säteilyfysiikka"
showing 10 items of 55 documents
SEU characterization of commercial and custom-designed SRAMs based on 90 nm technology and below
2020
International audience; The R2E project at CERN has tested a few commercial SRAMs and a custom-designed SRAM, whose data are complementary to various scientific publications. The experimental data include low- and high-energy protons, heavy ions, thermal, intermediate- and high-energy neutrons, high-energy electrons and high-energy pions.
Single-event effects of space and atmospheric radiation on memory components
2017
Electronic memories are ubiquitous components in electronic systems: they are used to store data, and can be found in all manner of industrial, automotive, aerospace, telecommunication and entertainment systems. Memory technology has seen a constant evolution since the first practical dynamic Random- Access Memories (dynamic RAMs) were created in the late 60's. The demand for ever-increasing performance and capacity and decrease in power consumption was met thanks to a steady miniaturization of the component features: modern memory devices include elements barely a few tens of atomic layers thick and a few hundred of atomic layers wide. The side effect of this constant miniaturization was a…
Technical note : Simulation of lung counting applications using Geant4
2023
A Geant4 simulation package has been developed to investigate and test detector configurations for lung counting applications. The objective of this study was to measure radiation emitted from the human body and to make a qualitative comparison of the results of the simulation with an experiment. Experimental data were measured from a plastic phantom with a set of lungs containing 241Am activity. For comparison, simulations in which 241Am activity was uniformly distributed inside the lungs of the ICRP adult reference computational phantom were made. The attenuation of photons by the chest wall was simulated and from this photopeak ef-ficiency and photon transmission were calculated as a fun…
New Capabilities of the FLUKA Multi-Purpose Code
2022
We would like to deeply thank the CERN Knowledge Transfer and Legal Service teams for their essential and extended support. Our appreciation also goes to the FLUKA.CERN Collaboration Board members for their strong commitment.
Development and use of computational tools for modelling negative hydrogen ion source extraction systems
2013
Direct Ionization Impact on Accelerator Mixed-Field Soft Error Rate
2020
We investigate, through measurements and simulations, the possible direct ionization impact in the accelerator soft error rate, not considered in standard qualification approaches. Results show that, for a broad variety of state-of-the art commercial components considered in the 65 nm to 16 nm technological range, indirect ionization is still expected to dominate the overall soft-error rate in the accelerator mixed-field. However, the derived critical charges of the most sensitive parts, corresponding to ∼0.7 fC, are expected to be at the limit of rapid direct ionization dominance and soft-error increase. peerReviewed
Radioluminescence Response of Ce-, Cu-, and Gd-Doped Silica Glasses for Dosimetry of Pulsed Electron Beams
2021
Radiation-induced emission of doped sol-gel silica glass samples was investigated under a pulsed 20-MeV electron beam. The studied samples were drawn rods doped with cerium, copper, or gadolinium ions, which were connected to multimode pure-silica core fibers to transport the induced luminescence from the irradiation area to a signal readout system. The luminescence pulses in the samples induced by the electron bunches were studied as a function of deposited dose per electron bunch. All the investigated samples were found to have a linear response in terms of luminescence as a function of electron bunch sizes between 10−5 Gy/bunch and 1.5×10−2 Gy/bunch. The presented results show that these…
Measurements of Low-Energy Protons using a Silicon Detector for Application to SEE Testing
2021
A silicon detector with a fast electronics chain is used for the dosimetry of protons in the range 0.5-5 MeV at the Centro Nacional de Aceleradores (CNA) 3 MV Tandem laboratory in Seville, Spain. In this configuration, measurements can be performed in pulsed mode, using a digitizer to record event-by-event proton energy depositions. The distributions of deposited energy were obtained thanks to a calibration with an alpha source. Measurements of flux and deposited energy are used to enable single event effect (SEE) testing on selected static random access memories (SRAMs).
Proton Direct Ionization in Sub-Micron Technologies : Test Methodologies and Modelling
2023
Two different low energy proton (LEP) test methods, one with quasi-monoenergetic and the other with very wide proton beam energy spectra, have been studied. The two test methodologies have been applied to devices that were suggested from prior heavy-ion tests to be sensitive to proton direct ionization (PDI). The advantages and disadvantages of the two test methods are discussed. The test method using quasi-monoenergetic beams requires device preparation and high energy resolution beams, but delivers results that can be interpreted directly and can be used in various soft error rate (SER) calculation methods. The other method, using a heavily degraded high energy proton beam, requires littl…
Mechanisms of Electron-Induced Single Event Upsets in Medical and Experimental Linacs
2018
In this paper, we perform an in-depth analysis of the single-event effects observed during testing at medical electron linacs and an experimental high-energy electron linac. For electron irradiations, the medical linacs are most commonly used due to their availability and flexibility. Whereas previous efforts were made to characterize the cross sections at higher energies, where the nuclear interaction cross section is higher, the focus of this paper is on the complete overview of relevant electron energies. Irradiations at an electron linac were made with two different devices, with a large difference in feature size. The irradiations at an experimental linac were performed with varying en…