Search

Your search keyword '"A. Belafrites"' showing total 35 results
Start Over Author "A. Belafrites"
35 results on '"A. Belafrites"'

5. Vies Moyennes Des Etats Excites Du 19F

Author

Belafrites, A., Boucenna, A., Benazzouz, C., and Benammar, M. A.

Subjects
Nuclear Experiment
Abstract

The determination of the mean lifetime of excited states has been undertaken by coulomb excitation that is a process of inelastic scattering in which the incident particle is charged and provokes an excitation of the target nucleus by mean of the electromagnetic fields during the passage of the projectile. The cross section of this inelastic scattering is proportional to the width of the isomeric state. The mean lifetime of excited states of the 19F are determined by comparing the experimental results of reactions 19F(alpha,alpha' gamma)19F and 19F(p, p' gamma)19F with the theoretical calculations achieved with the help of the multiple coulomb excitation program Coulex. These mean lifetimes are compared to those restraints by Ajzenberg - Selove [1] and Alder and al. [2]., Comment: 11 pages, 10 figures, 6 tables, in French

Published
2003

15. Single- and Double-Strand Breaks of Dry DNA Exposed to Protons at Bragg-Peak Energies

Author

Michel Fromm, Dominique Muller, A. Belafrites, Rémi Barillon, Quentin Raffy, Mounir Souici, Talat Tariq Khalil, Christophe Champion, Laboratoire de Physique des Rayonnements et Applications (LPRA), Université Mohammed Seddik Benyahia [Jijel] | University of Jijel (UMSBJ), Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie (ICube), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Les Hôpitaux Universitaires de Strasbourg (HUS)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Département Recherches Subatomiques (DRS-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Programme National Exceptionnel (PNE - French Algerian Collaboration program), Université Mohamed Seddik Ben Yahia [Jijel], Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Rayonnements et Applications ( LPRA ), Université de Jijel, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie ( ICube ), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg ( ENGEES ) -Université de Strasbourg ( UNISTRA ) -Institut National des Sciences Appliquées - Strasbourg ( INSA Strasbourg ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ) -Matériaux et nanosciences d'Alsace, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Réseau nanophotonique et optique, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ), Département Recherches Subatomiques ( DRS-IPHC ), Institut Pluridisciplinaire Hubert Curien ( IPHC ), Université de Strasbourg ( UNISTRA ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ) -Centre National de la Recherche Scientifique ( CNRS ), Centre d'Etudes Nucléaires de Bordeaux Gradignan ( CENBG ), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
cross-section, Proton, Polyesters, Linear energy transfer, Bragg peak, 7. Clean energy, clustered DNA damage, 030218 nuclear medicine & medical imaging, damage yield, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Fragmentation (mass spectrometry), Materials Chemistry, DNA Breaks, Double-Stranded, Linear Energy Transfer, DNA Breaks, Single-Stranded, Irradiation, Physical and Theoretical Chemistry, radiochemical yield, Double strand, Range (particle radiation), DNA, Surfaces, Coatings and Films, [ PHYS.PHYS.PHYS-CHEM-PH ] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], chemistry, 030220 oncology & carcinogenesis, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Protons, Atomic physics, Plasmids, Bragg-Peak, single and double strand break
Abstract

International audience; Ultrathin layers (

Published
2017

19. DNA strand break dependence on Tris and arginine scavenger concentrations under ultra-soft X-ray irradiation: the contribution of secondary arginine radicals

Author

A. Belafrites, Talat Tariq Khalil, Omar Boulanouar, Mounir Souici, Michel Fromm, and Christophe Mavon

Subjects
Tris, Free Radicals, Arginine, DNA damage, Radical, Biophysics, Photochemistry, DNA Strand Break, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Tromethamine, General Environmental Science, Gel electrophoresis, Radiation, Aqueous solution, Dose-Response Relationship, Drug, Chemistry, X-Rays, DNA Breaks, Free Radical Scavengers, Biochemistry, 030220 oncology & carcinogenesis, DNA, Plasmids
Abstract

In this study, we used a bench-top cold-cathode ultra-soft X-ray (USX) generator to expose aqueous DNA plasmid solutions to low-LET radiation under various scavenging conditions. Single- and double-strand breaks were assessed using classic gel electrophoresis quantification of linear, circular and supercoiled plasmid DNA topologies. With their very low penetration range in water, USX can only interact with matter up to short distances, of the order of 50 μm. We validated a stirring procedure which makes it possible to expose 100 µL of aqueous samples (2 mm thick). The scavenging of OH radicals by Tris buffer was studied at ambient temperature under aerobic conditions and compared to data gathered in the literature. A very good agreement was found with the rare data dealing with DNA plasmid exposed to Al Kα photons at low temperature (T ≤ 277 K), which therefore validated the experimental procedure. The yields for DNA single-strand breaks determined during this study enabled the ratio of indirect to direct effects to be determined at 96.2%, in good agreement with the value of 97.7% stemming from a study based on γ-ray irradiation of frozen solutions of plasmid DNA. Then, arginine was used both to create a "biological-like" chemical environment around the DNA plasmids and as an OH radical scavenger, in vitro. Although arginine has a greater scavenging (protecting) power than Tris, surprisingly, it led to higher rates of strand breakage. Based on the specific binding modes of arginine to DNA, we suggest that the side effects observed are due to the presence of arginine near to, but also inside, the DNA double helix.

Published
2016

20. Evaluation of radionuclide concentrations and external gamma radiation levels in phosphate ores and fertilizers commonly used in Algeria

Author

A. Tedjani, J.-E. Groetz, Christophe Mavon, D. Boumala, A. Belafrites, Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)

Subjects
Health, Toxicology and Mutagenesis, chemistry.chemical_element, engineering.material, Potassium-40, 010403 inorganic & nuclear chemistry, 01 natural sciences, Effective dose (radiation), 030218 nuclear medicine & medical imaging, Analytical Chemistry, Radium, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Radiology, Nuclear Medicine and imaging, Spectroscopy, ComputingMilieux_MISCELLANEOUS, Radionuclide, Radiochemistry, Public Health, Environmental and Occupational Health, Thorium, Phosphate, Pollution, 0104 chemical sciences, Nuclear Energy and Engineering, chemistry, 13. Climate action, Absorbed dose, [SDE]Environmental Sciences, engineering, Fertilizer
Abstract

In this paper, radionuclide concentrations of 226Ra, 232Th and 40K contained in two phosphate ores and six granular fertilizer samples were determined using gamma-ray spectrometry. The mean activity concentrations of 226Ra, 232Th and 40K were found to be 255 ± 12, 193 ± 7 and 23 ± 6 Bq kg−1, respectively, in phosphate ores and 86 ± 4, 12 ± 2 and 1348 ± 95 Bq kg−1, respectively, in phosphate fertilizers. The total absorbed dose rates in air (D) calculated from the concentrations of the three radionuclides ranged from 14 to 297 nGy year−1, and the external annual effective dose rates (AEDR) were determined to be between 0.01 and 0.36 mSv year−1. Based on the annual effective dose calculations, the estimated excess lifetime cancer risks due to phosphate ores and phosphate fertilizers are 1.02 × 10−3 and 0.42 × 10−3, respectively. The mean values of radium equivalent activity (Raeq), external hazard index (Hex), and internal hazard index (Hin) were also calculated, and their mean values are 532 Bq kg−1, 1.9 and 2.25 respectively, in phosphate ores and 205 Bq kg−1, 0.55 and 0.78, respectively, in fertilizers. Results were discussed and compared with those reported in similar studies and with internationally recommended values.

Published
2018

21. Spatial distribution of air kerma rate and impact of accelerating voltage on the quality of an ultra soft X-ray beam generated by a cold cathode tube in air

Author

Michel Fromm, A. Belafrites, N. Ounoughi, and Christophe Mavon

Subjects
Physics, Radiation, business.industry, X-ray tube, Acceleration voltage, Cathode, law.invention, Anode, Kerma, Optics, law, Ionization chamber, Cold cathode, Atomic physics, business, Instrumentation, Beam (structure)
Abstract

Ultrasoft X-ray characteristic aluminum K alpha line (Al Kα with energy of 1.5 keV) is used in radiobiological experiments to study the effect of radiation on biological matter. A simple method to generate a continuous beam of those X-ray radiations is to bombarding an aluminum target with accelerated electrons using high voltage (HV). In this work, by varying the HV we study the characteristics of a photon beam generated by means of a cold cathode transmission X-ray tube. The anode is a thin (16 μm) aluminum foil supported by a copper grid. The spatial distribution of air kerma is measured using gafchromic films of HD-810 calibrated with a parallel plate free-air ionization chamber. We show that HV strongly modifies the energetic spectrum and air kerma rate as well as its uniformity and intensity in air.

Published
2015

22. Well GeHP detector calibration for environmental measurements using reference materials

Author

A. Tedjani, Christophe Mavon, D. Boumala, D. Degrelle, A. Belafrites, J.-E. Groetz, Damien Rius, Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire de Physique des Rayonnements et Applications (LPRA), Université Mohamed Seddik Ben Yahia [Jijel], Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Laboratoire de Physique des Rayonnements et Applications ( LPRA ), and Université de Jijel

Subjects
Nuclear and High Energy Physics, Monte Carlo method, Well-type detector, 010403 inorganic & nuclear chemistry, 01 natural sciences, Coincidence, Particle detector, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Optics, True coincidence summing, Full energy peak efficiency, Calibration, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Instrumentation, [ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Remote sensing, Physics, business.industry, Detector, 0104 chemical sciences, Semiconductor detector, Measuring instrument, business, Efficiency correction, Energy (signal processing), MCNP6
Abstract

International audience; A well-type detector installed in the Modane underground Laboratory (LSM) can combine both low background and high detection efficiency and it is well suited for the analysis of small amounts of environmental samples. Reference materials such as IAEA-447 (moss-soil), IAEA-RG-Th1 and IAEA-RG-U1 were used for the detector calibration, owing to a chemical composition close to those of the environmental samples. Nevertheless , the matrix effects and the true coincidence summing effects must be corrected from the full energy peak efficiency (FEPE). The FEPE was performed for a wide range of energy by a semi-empirical method using Monte Carlo simulation (MCNP6), intended for environmental measurements such as lake sediments dating. In the well geometry, the true coincidence summing effects could be very important and correction factors have been computed in three different ways.

Published
2016

23. Dependence of PN3 response to Am–Be neutrons on etching and reading process

Author

Abdel-Mjid Nourreddine, Th. Lê, M. Trocmé, S. Higueret, A. Belafrites, Département Recherches Subatomiques (DRS-IPHC), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics::Instrumentation and Detectors, Instrumentation, Nuclear Theory, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Recoil, Optics, Etching (microfabrication), Radiation damage, Dose equivalent response, Neutron, ECE, Nuclear Experiment, Radiation, business.industry, Equivalent dose, Chemistry, Automated etching system, Detector, Fast neutron dosimetry, Isotropic etching, CE, Scanning system, PN3 detector, 030220 oncology & carcinogenesis, business, [CHIM.RADIO]Chemical Sciences/Radiochemistry, Nuclear chemistry
Abstract

International audience; Polyallyl diglycol carbonate can be polymerized to make solid-state nuclear track detectors, type PN3, that are widely used for neutron dosimetry. Neutrons are detected by the damage trails created by recoil nuclei of the PN3 constituent atoms that are subsequently revealed by either a suitable chemical etching (CE) or electrochemical etching (ECE) process. On the basis of calibration exposures, track density can be related to neutron dose equivalent. The dose equivalent response and the detection level depend on detector material, nature and thickness of the radiator, energy and angle of incidence of the neutron, and the etching process. An automated ECE and reading system has been developed in RaMsEs laboratory. We compare the PN3 neutron dose equivalent response to 241Am–Be neutrons without radiator for both CE and ECE

Published
2008

25. Response of PN3 dosimeters to –Be neutrons

Author

Abdel-Mjid Nourreddine, A. Nachab, D. Mouhssine, A. Belafrites, and A. Boucenna

Subjects
Neutron dose, Radiation, Dosimeter, Materials science, business.industry, Neutron dosimeter, Radiochemistry, Detector, law.invention, Optics, law, Neutron, Radiator, business, Instrumentation
Abstract

CR-39 type PN3 plastic detectors associated with a polyethylene or PN3 radiator or without radiator were exposed to Pu–Be neutrons to evaluate their effectiveness as fast neutron dosimeters. The detectors were chemically etched and track counting was performed using an automated system. It was found that the dosimeter responses were linear up to a neutron dose equivalent of 200 mSv and that the simple PN3 detector without radiator has the same response as the two-element dosimeters and thus appears as a promising fast neutron dosimeter.

Published
2005

26. Conception and realization of a parallel-plate free-air ionization chamber for the absolute dosimetry of an ultrasoft X-ray beam

Author

Michel Fromm, Nabil Ounoughi, J.-E. Groetz, A. Belafrites, Christophe Mavon, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), LPRA, Laboratoire de Physique des Rayonnements et Applications ( LPRA ), Université de Jijel-Université de Jijel, Université de Jijel, Financement partiel CNOUS France-Algerie, Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire de Physique des Rayonnements et Applications (LPRA), Université Mohamed Seddik Ben Yahia [Jijel]-Université Mohamed Seddik Ben Yahia [Jijel], and Université Mohamed Seddik Ben Yahia [Jijel]

Subjects
Physics, Air Ionization, Photon, X-Rays, Monte Carlo method, Models, Theoretical, Particle detector, Computational physics, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Kerma, Ionization chamber, [ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry, Dosimetry, Atomic physics, Radiometry, Instrumentation, Beam (structure)
Abstract

International audience; We report the design of a millimeter-sized parallel plate free-air ionization chamber 10 (IC) aimed at determining the absolute air kerma rate of an ultra-soft X-ray beam (E = 1.5 keV). The size of the IC was determined so that the measurement volume satisfies the condition of charged-particle equilibrium. The correction factors nec-essary to properly measure the absolute kerma using the IC have been established. Particular attention was given to the determination of the effective mean energy 15 for the 1.5 keV photons using the PENELOPE code. Other correction factors were determined by means of computer simulation (COMSOL and FLUKA). Measure-ments of air kerma rates under specific operating parameters of the lab-bench X-ray source have been performed at various distances from that source and compared to Monte-Carlo calculations. We show that the developed ionization chamber makes it 20 possible to determine accurate photon fluence rates in routine work and will consti-tute substantial time-savings for future radiobiological experiments based on the use of ultra-soft X-rays.

Published
2014

27. Beam characterization of a lab bench cold cathode ultra-soft X-ray generator

Author

Michel Fromm, A. Belafrites, Christophe Mavon, Nabil Ounoughi, J.-E. Groetz, LPRA, Laboratoire de Physique des Rayonnements et Applications ( LPRA ), Université de Jijel-Université de Jijel, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Université de Jijel, Interactions rayonnements-matière, Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ) -Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Laboratoire de Physique des Rayonnements et Applications (LPRA), Université Mohamed Seddik Ben Yahia [Jijel]-Université Mohamed Seddik Ben Yahia [Jijel], Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), and Université Mohamed Seddik Ben Yahia [Jijel]

Subjects
Nuclear and High Energy Physics, Materials science, Physics::Instrumentation and Detectors, Acceleration voltage, Ultra-soft X-rays (USX), 030218 nuclear medicine & medical imaging, law.invention, 03 medical and health sciences, 0302 clinical medicine, Optics, law, Aluminium foil, Physics::Plasma Physics, USX cold cathode generator, Instrumentation, FOIL method, business.industry, Gafchromic dosimetry, Cathode, Anode, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, 030220 oncology & carcinogenesis, [ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry, Cathode ray, Cold cathode, Physics::Accelerator Physics, Aluminium Kα line, Atomic physics, business, Beam (structure)
Abstract

International audience; The aim of this work is to characterize the Ultra Soft X-ray (USX, 1.5 keV, Al Kα) photon beam of a customized lab bench cold cathode generator. Within this generator, the electron beam is slowed down in a thin aluminium foil (16 μm) supported by an easily exchangeable anode. It is shown that the thickness of the foil and the anode configuration determine the spatial distribution and the fluence rate of the photon beam, whereas accelerating voltage determines both fluence rate and energy spectrum feature. It is shown also that under specific operation parameters (i.e. accelerating voltage), a Gaussian energy distribution of the beam can be generated which is centred on the energy of the Al Kα line (1.5 keV). Dosimetric films of GAFCHROMIC® HD-810 were used to estimate the photon fluence rate distribution of the beam. Its variation, when the generator acts as a monoenergetic source, was characterized with the two different configurations of the anode assembly. Finally, it is verified that the anode assembly consisting in a flat washer, on which the aluminium foil is set, acts as a simple point-source.

Published
2013

28. Etude et caractérisation d'un dosimètre neutrons rapides à base de PADC - Study and characterization of a fast neutron dosimeter based on PADC

Author

Belafrites, A., Higueret, S., Nourreddine, A., Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), and Heyd, Yvette

Subjects
Fonction de réponse, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [CHIM.THEO] Chemical Sciences/Theoretical and/or physical chemistry, Dosimétrie des neutrons rapides, [PHYS.PHYS.PHYS-INS-DET] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Fast neutron dosimetry, Track detector, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Polyethylene radiator, Radiateur polyéthylène, Response function Détecteur solide de traces nucléaires
Abstract

Polyallyl Diglycol Carbonate (PADC) type PN3 is a polymeric solid state nuclear track detector which is widely used for neutron dosimetry. In this paper, we present the response of PN3 dosimeters for use in fast neutron measurements. PN3 detectors associated with a polyethylene (PE) or PN3 radiator or without radiator were exposed to Am-Be neutrons to evaluate their effectiveness as fast neutron dosimeters. The detectors were chemically etched and track counting was performed using an automated system. It was found that the dosimeter responses were linear up to a neutron dose equivalent of at least 200 mSv and that the simple PN3 detector without radiator (but after pre-etch) has the same response as the two-element dosimeters and thus appears as a promising fast neutron dosimeter Le Polyallyl Diglycol Carbonate (PADC) de type PN3 est un détecteur solide de traces nucléaires qui est largement utilisé en dosimétrie neutrons. Dans ce travail, nous avons étudié la réponse des dosimètres PN3 pour la détection des neutrons rapides. Trois dosimètres constitués d'un détecteur PN3 sans radiateur, d'un détecteur PN3 associé à un radiateur en polyéthylène (PE) et d'un détecteur PN3 associé à un autre détecteur PN3 comme radiateur ont été exposé à une source de neutrons Am-Be. Ces détecteurs ont été développés chimiquement et le comptage de traces a été effectué par système semi automatique. Les résultats obtenus montrent que la fonction de réponse des dosimètres est linéaire en fonction d'équivalent de dose jusqu'au 200 mSv et que le dosimètre PN3 sans radiateur présente une réponse comparable aux deux autres dosimètres et prouve qu'il pourrait être utilisé comme au dosimètre personnel des neutrons rapides

Published
2008

29. A joint UAB-IReS-IPNO neutron comparison exercise with nuclear track detectors

Author

Carles Domingo, Abdel-Mjid Nourreddine, M.J. García, I. Ribaud, D. Mouhssine, A. Belafrites, K. Amgarou, F. Fernández, Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), F. Fernández, R. Ilić, Ll. Font, and C. Domingo

Subjects
Physics, PADC nuclear track detectors, Radiation, Equivalent dose, Radiochemistry, Detector, Intercomparison exercise, Neutron dosimetry, Imaging phantom, 030218 nuclear medicine & medical imaging, Nuclear physics, 03 medical and health sciences, 0302 clinical medicine, 030220 oncology & carcinogenesis, Electromagnetic shielding, Calibration, Neutron source, Neutron, Irradiation, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Instrumentation
Abstract

The response of PN3 and CR-39 personal dosemeters with different configurations, developed by the IReS (Strasbourg), the IPNO (Orsay) and the UAB (Barcelona) groups, is investigated in this study. Both dosemeters were mounted on a water-filled phantom and were simultaneously exposed under different incidence angles ( 0 ∘ , 30 ∘ and 60 ∘ ) to the following: (i) three ISO neutron sources ( 241 Am-Be, bare 252 Cf and moderated 252 Cf with Cd shielding), and (ii) two realistic neutron sources (SIGMA and moderated 252 Cf) at the IRSN (Cadarache) facilities. After irradiation, the plastic detectors were etched and evaluated according to local routine procedures and corrections for the effect of source-to-detector distance were taken into account. A comparison of the average background, the minimum detectable dose equivalent and the field calibration factor is performed as well.

Published
2004

30. Fast neutron response of a personal dosimeter based on PN3 track detectors - Reponse d'un dosimetre personnel a base de DSTN type PN3 aux neutrons rapides

Author

Belafrites, A., Nourreddine, A., Mouhssine, D., Nachab, A., Boucenna, A., Heyd, Yvette, Institut de Recherches Subatomiques (IReS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published
2004

31. Response of PN3 dosimeters to $^{239}$Pu-Be neutrons

Author

Belafrites, A., Nourreddine, A., Mouhssine, D., Nachab, A., Boucenna, A., Institut de Recherches Subatomiques (IReS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Cancéropôle du Grand Est-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), and Elsevier Ltd

Subjects
[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Published
2004

Catalog

Books, media, physical & digital resources
See catalog results