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Ramonville-Saint-Agne, France

Sanchez-Doblado F.,Hospital Universitario Virgen Macarena | Sanchez-Doblado F.,University of Seville | Domingo C.,Autonomous University of Barcelona | Gomez F.,University of Santiago de Compostela | And 28 more authors.
Physics in Medicine and Biology | Year: 2012

Neutron peripheral contamination in patients undergoing high-energy photon radiotherapy is considered as a risk factor for secondary cancer induction. Organ-specific neutron-equivalent dose estimation is therefore essential for a reasonable assessment of these associated risks. This work aimed to develop a method to estimate neutron-equivalent doses in multiple organs of radiotherapy patients. The method involved the convolution, at 16 reference points in an anthropomorphic phantom, of the normalized Monte Carlo neutron fluence energy spectra with the kerma and energy-dependent radiation weighting factor. This was then scaled with the total neutron fluence measured with passive detectors, at the same reference points, in order to obtain the equivalent doses in organs. The latter were correlated with the readings of a neutron digital detector located inside the treatment room during phantom irradiation. This digital detector, designed and developed by our group, integrates the thermal neutron fluence. The correlation model, applied to the digital detector readings during patient irradiation, enables the online estimation of neutron-equivalent doses in organs. The model takes into account the specific irradiation site, the field parameters (energy, field size, angle incidence, etc) and the installation (linac and bunker geometry). This method, which is suitable for routine clinical use, will help to systematically generate the dosimetric data essential for the improvement of current risk-estimation models. © 2012 Institute of Physics and Engineering in Medicine. Source


Kettunen H.,University of Jyvaskyla | Ferlet-Cavrois V.,European Space Agency | Roche P.,STMicroelectronics | Rossi M.,University of Jyvaskyla | And 7 more authors.
IEEE Radiation Effects Data Workshop | Year: 2014

A low energy proton facility has been developed at RADEF, Jyväskylä, Finland. The proton energy selection, calibration and dosimetry are described. The first experiment with external users was performed using two memory test vehicles fabricated with 28 nm technology. Examples of single event upset measurements in the test vehicles embedded SRAMs (eSRAMs) as a function of proton energy are provided. © 2014 IEEE. Source


Harboe-Sorensen R.,RHS Consultant | Poivey C.,European Space Agency | Zadeh A.,European Space Agency | Keating A.,European Space Agency | And 7 more authors.
IEEE Transactions on Nuclear Science | Year: 2012

A Technology Demonstration Module (TDM) to monitor radiation effects in semiconductor devices was part of the payload on-board the European Space Agency (ESA) PROBA-II satellite. PROBA-II was launched on November 2nd 2009, into an 800 km polar orbit with the TDM switched-on since February 15th 2010. The TDM primarily carries modern memory devices in order to monitor and record their Single Event Effect (SEE) behavior in respect to orbital positions. This paper presents a first set of in-flight data obtained between February 15th 2010 and March 31st 2011. Emphases were placed on validation of the various experiments and not on data analysis itself. Observed in-flight error rates are compared with predictions based on ground test data obtained on flight lot devices operating under identical conditions. © 2012 IEEE. Source


Harboe-Sorensen R.,RHS Consultant | Poivey C.,European Space Agency | Fleurinck N.,QinetiQ | Puimege K.,QinetiQ | And 9 more authors.
IEEE Transactions on Nuclear Science | Year: 2011

As a semiconductor component radiation effects and technology demonstration experiment, the Technology Demonstration Module (TDM) integrated into the PROBA-II satellite, was launched on November 2nd 2009, into a 800 km polar orbit. This SEU/SEL experiment, in strong support to the Reference SEU Monitor database , will be described and details given about ground testing and calibrations. Since ground testing was carried out on flight lot devices and under flight operational conditions, the in-orbit SEU/SEL database will eventually become a vital reference point for improved modeling, prediction and testing. Evidence to confirm this promise is starting to emerge and will be presented at the end of the paper. As the present in-orbit number of events is still small, only the first month of flight performance will be presented with strong emphasis on validating correct operation of monitored devices. © 2010 IEEE. Source


D'Alessio M.,European Space Agency | Poivey C.,European Space Agency | Ferlet-Cavrois V.,European Space Agency | Evans H.,European Space Agency | And 15 more authors.
Proceedings of the European Conference on Radiation and its Effects on Components and Systems, RADECS | Year: 2013

This paper presents an analysis of the SEE in-flight data of SRAMs on board Proba-II spacecraft. Proba-II spacecraft has been flying on a LEO orbit for more than 3 years. Observed in-flight error rates are compared with predictions based on ground test data. © 2013 IEEE. Source

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