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36 results on '"M. M. Aléonard"'

1. Experimental and Monte Carlo absolute characterization of a medical electron beam using a magnetic spectrometer

Author

P. Barberet, I. Bessieres, D. Denis-Petit, T. Bonnet, M. Tarisien, J. J. Santos, Jean-Luc Feugeas, Jerome Caron, M. Versteegen, M. Comet, M. M. Aléonard, F. Hannachi, Guy Kantor, S. Hulin, F. Gobet, Philippe Nicolai, Vladimir Tikhonchuk, M. Antoine, 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
Electron spectrometer, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Monte Carlo method, Physics::Medical Physics, Analytical chemistry, Electron, Position sensitive detectors, 01 natural sciences, Imaging phantom, 010305 fluids & plasmas, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, 0103 physical sciences, Instrumentation, Physics, Radiation, Spectrometer, Isocenter, Monte Carlo methods, Radiation control, Computational physics, Measuring instrument, Cathode ray, Physics::Accelerator Physics, Accelerators
Abstract

International audience; The knowledge of the absolute energy distributions of the particles emitted from a clinical accelerator is important for the evaluation of Monte Carlo simulations developed for treatment planning. In this paper, an original approach is presented which allows to measure the absolute energy distribution of the electron beam delivered by a Varian 21Ex medical accelerator. The electron beam was characterized at the isocenter with calibrated image plates covering the exit window of a magnetic spectrometer. The characteristics of the electron beam emitted from an effective source have been inferred from the measurements using the Geant4 Monte Carlo code. The contribution of direct electrons to the absolute depth-dose curve in a water phantom is estimated.

Published
2016
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2. Prospects for nuclear physics with lasers

Author

M. M. Aléonard, M. Gerbaux, Erik Brambrink, J. N. Scheurer, V. Méot, Vladimir Tikhonchuk, P. Morel, C. Plaisir, M. Tarisien, Ph. Nicolaï, G. Malka, F. Gobet, F. Hannachi, P. Audebert, 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), Laboratoire pour l'utilisation des lasers intenses (LULI), Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-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), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB)

Subjects
Nuclear reaction, Photon, Nuclear Theory, Population, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Particle detector, law.invention, Nuclear physics, law, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Nuclear Experiment, 010306 general physics, education, Physics, education.field_of_study, 010308 nuclear & particles physics, Particle accelerator, Plasma, Condensed Matter Physics, Laser, Nuclear Energy and Engineering, 13. Climate action
Abstract

The development of high intensity lasers has opened up new opportunities for nuclear physics studies in extreme conditions which cannot be reached with conventional particle accelerators. A laser is a unique tool to produce plasma and very high fluxes of photon and particle beams in very short duration pulses. Both aspects are of great interest for fundamental nuclear physics studies. In plasma the electron–ions collisions may modify atomic and nuclear level properties. This is of prime importance for the population of isomeric states and the issue of energy storage in nuclei. Nuclear properties in the presence of very high electromagnetic fields, nuclear reaction rates or properties in hot and dense plasmas are new domains of investigation. Our group has launched an experimental program to evaluate the possibilities for such nuclear physics studies at high intensity laser facilities. This program and its first results are presented.

Published
2007
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3. Energy sharing in the deexcitation of the90Ru compound nucleus via thepαchannel

Author

G. Barreau, A. Principe, A. Brondi, M. M. Aléonard, J. N. Scheurer, M. Harston, J.P. Goudour, D. Cabaussel, D. Curien, D. Boivin, M. Aiche, F. Bourgine, R. Moro, G. La Rana, J.F. Chemin, Emanuele Vardaci, and T.P. Doan

Subjects
Physics, Nuclear and High Energy Physics, Angular momentum, Spectrometer, Available energy, Evaporation, Alpha particle, Atomic physics, Charged particle, Energy (signal processing), Excitation
Abstract

Using the 4$\ensuremath{\pi}$ light charged-particle detector DIAMANT in combination with the $\ensuremath{\gamma}$-ray spectrometer EUROGAM II, the decay of the ${}^{90}$Ru compound nucleus via the $p\ensuremath{\alpha}$ channel was studied. These nuclei were produced at an excitation energy of 54.9 MeV and with a maximum angular momentum of 37$\ensuremath{\Elzxh}$ by the 120 MeV ${}^{32}$S + ${}^{58}$Ni reaction. The measurement of the energy of the two particles allowed the determination of the energy distribution of the entry states. A particular behavior of the sharing of the available energy between the two particles was found: For increasing values of the entry-state energy, the mean energy for protons remains almost constant while for alpha particles it decreases. This behavior is well reproduced by the evaporation code LILITA_N95. The physics underlying the decay is discussed in the framework of the statistical model which predicts a strong correlation between the excitation energy and the angular momentum of the evaporation residue. This result encourages the use of the $p\ensuremath{\alpha}$ channel to select the excitation energy and the angular momentum of the evaporation residue for superdeformed band studies.

Published
1997
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4. Improvements in the in-beam γ-ray spectroscopy provided by an ancillary detector coupled to a Ge γ-spectrometer: the DIAMANT-EUROGAM II example

Author

D. Curien, A. Brondi, J. N. Scheurer, M. Harston, T.P. Doan, M. M. Aléonard, J.F. Chemin, D. Boivin, R. Moro, F. Bourgine, D. Cabaussel, M. Aiche, Emanuele Vardaci, G. La Rana, J.P. Goudour, G. Barreau, J. N., Scheurer, M., Aiche, M. M., Aleonard, G., Barreau, F., Bourgine, D., Boivin, D., Cabaussel, J. F., Chemin, T. P., Doan, J. P., Goudour, M., Harston, Brondi, Augusto, LA RANA, Giovanni, Moro, RENATA EMILIA MARIA, Vardaci, Emanuele, and D., Curien

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, business.industry, Detector, scintillation detector, Scintillator, Doppler shift correction, gamma ray spectroscopy, Charged particle, Nuclear physics, symbols.namesake, Optics, symbols, Gamma spectroscopy, Spectroscopy, business, charged particle spectrometer, Instrumentation, Doppler effect, Beam (structure)
Abstract

For the first time the 4π γ-ray spectrometer EUROGAM II has been coupled to a 4π light charged particle detector array, DIAMANT, during a test experiment on the reaction 32 S + 58 Ni at 120 MeV beam energy. A very large improvement in the peak-to-background ratio of the γ-spectra has been found when EUROGAM II is triggered by DIAMANT to select an exit channel. A simple algebra has been developed which provides theoretical estimates in good agreement with these experimental results. It is demonstrated that, depending on both the γ-spectrometer and ancillary detector performances, much better peak-to-background can be obtained by such a coupling. For the same peak-to-background ratio, the use of an ancillary detector allows for a lower γ-ray coincidence level and therefore improves the statistics. Ways to select the most appropriate ancillary detector are given. The ability of the ancillary detector to provide a total Doppler shift correction is crucial for the improvement of the peak-to-background ratio.

Published
1997
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5. Insights on the population of the superdeformed bands using the EUROGAMII – DIAMANT apparatus

Author

G. LA RANA, A. BRONDI, R. MORO, E. VARDACI, M. AICHE, M. M. ALÉONARD, G. BARREAU, D. BOIVIN, F. BOURGINE, J. F. CHEMIN, J. N. SCHEURER, D. CURIEN, G. DUCHENE, F. A. BECK, B. HAAS, J. P. VIVIEN, G. DE FRANCE, F. HANNACHI, K Yoshida, S Kubono, I Tanihata, C Signorini, LA RANA, Giovanni, Brondi, Augusto, Moro, RENATA EMILIA MARIA, Vardaci, Emanuele, M., Aiche, M. M., Aléonard, G., Barreau, D., Boivin, F., Bourgine, J. F., Chemin, J. N., Scheurer, D., Curien, G., Duchene, F. A., Beck, B., Haa, J. P., Vivien, G., DE FRANCE, and F., Hannachi

Subjects
Nuclear physics, Physics, Particle physics, education.field_of_study, superdeformed band, Population, EUROGAM, education, ancillary detector, DIAMANT
Abstract

Experiments to study the decay of hot composite nuclei have been carried out with EUROGAM II γ-ray spectrometer, coupled to the DIAMANT charged-particle detector, at the VIVITRON accelerator at IReS in Strasbourg. Some relevant aspects related to the population of superdeformed bands have been addressed, on the basis of very exclusive data. We present the results for the composite nuclei 90Ru and 160Er produced in the reactions 120, 130 MeV 32S + 58Ni, and 191 MeV 37Cl + 123Sb, at excitation energies Ex≅ 55, 61 and 92 MeV, respectively Evidence is given of effects related to the angular momentum as well as to the location of the entry region.

Published
2003

6. Response functions of imaging plates to photons, electrons and 4He particles

Author

F. Hannachi, M. M. Aléonard, M. Comet, F. Gobet, T. Bonnet, M. Versteegen, M. Tarisien, D. Denis-Petit, Excitations Nucléaires par Laser (ENL), 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)-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
Physics, Range (particle radiation), Photon, Elementary particle, Electron, 01 natural sciences, Particle detector, 010305 fluids & plasmas, Baryon, 0103 physical sciences, Particle, Stopping power (particle radiation), [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Atomic physics, 010306 general physics, Instrumentation
Abstract

Imaging plates from Fuji (BAS-SR, MS, and TR types) are phosphor films routinely used in ultra high intensity laser experiments. However, few data are available on the absolute IP response functions to ionizing particles. We have previously measured and modeled the IP response functions to protons. We focus here on the determination of the responses to photons, electrons, and (4)He particles. The response functions are obtained on an energy range going from a few tens of keV to a few tens of MeV and are compared to available data. The IP sensitivities to the different ionizing particles demonstrate a quenching effect depending on the particle stopping power.

Published
2013
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7. Response functions of Fuji imaging plates to monoenergetic protons in the energy range 0.6-3.2 MeV

Author

M. M. Aléonard, M. Tarisien, F. Hannachi, M. Versteegen, M. Comet, D. Denis-Petit, F. Gobet, T. Bonnet, Excitations Nucléaires par Laser (ENL), 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)-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
Physics, Range (particle radiation), Proton, Hadron, 01 natural sciences, Particle detector, 010305 fluids & plasmas, Baryon, Nuclear physics, 0103 physical sciences, Irradiation, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, Luminescence, Nucleon, Instrumentation
Abstract

We have measured the responses of Fuji MS, SR, and TR imaging plates (IPs) to protons with energies ranging from 0.6 to 3.2 MeV. Monoenergetic protons were produced with the 3.5 MV AIFIRA (Applications Interdisciplinaires de Faisceaux d'Ions en Région Aquitaine) accelerator at the Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG). The IPs were irradiated with protons backscattered off a tantalum target. We present the photo-stimulated luminescence response of the IPs together with the fading measurements for these IPs. A method is applied to allow correction of fading effects for variable proton irradiation duration. Using the IP fading corrections, a model of the IP response function to protons was developed. The model enables extrapolation of the IP response to protons up to proton energies of 10 MeV. Our work is finally compared to previous works conducted on Fuji TR IP response to protons.

Published
2013
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9. Measurement of the 85Rb(γ, n)84mRb cross-section in the energy range 10-19 MeV with bremsstrahlung photons

Author

M. Tarisien, G. Gosselin, M. M. Aléonard, B. Morillon, P. Morel, V. Méot, F. Gobet, C. Plaisir, F. Hannachi, Excitations Nucléaires par Laser (ENL), 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)-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), 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), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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)-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), 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
Physics, Nuclear and High Energy Physics, Photon, 010308 nuclear & particles physics, Hadron, Bremsstrahlung, chemistry.chemical_element, Particle accelerator, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Rubidium, law.invention, Nuclear physics, chemistry, law, 0103 physical sciences, Nuclear fusion, Irradiation, Atomic physics, 010306 general physics
Abstract

The 85Rb (\( \gamma\) ,n) 84mRb cross-section has been measured with bremsstrahlung photons at the CEA/DAM ELSA electron accelerator. Electrons with energies ranging from 10 to 19 MeV have been used. Natural rubidium chloride, gold and copper samples have been irradiated at the same time. The well-known activation standards 197Au (\( \gamma\) ,n) and 63Cu (\( \gamma\) ,n) reaction cross-sections have been used to validate the experimental method and the data analysis based on the GEANT4 simulation code. Our results are compared to available experimental data.

Published
2012
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10. Nuclear physics studies using high energy lasers

Author

M. Versteegen, G. Gosselin, C. Plaisir, P. Morel, M. M. Aléonard, M. Tarisien, F. Hannachi, V. Méot, F. Gobet, T. Bonnet, Excitations Nucléaires par Laser (ENL), 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)-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), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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)-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
Nuclear and High Energy Physics, Thermodynamic equilibrium, Nuclear Theory, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Molecular electronic transition, law.invention, Nuclear physics, law, 0103 physical sciences, medicine, 010306 general physics, Nuclear Experiment, Instrumentation, Physics, Laser plasma, Transition rates, 010308 nuclear & particles physics, Mode (statistics), Nuclear excitations, Plasma, Laser, 3. Good health, medicine.anatomical_structure, Atomic physics, Ground state, Nucleus, Excitation
Abstract

This paper presents several mechanisms expected to be responsible for nuclear excitation in laser-heated plasma. Attempts to detect such processes in nuclei initially in their ground state are discussed in 181Ta and 235U cases. A calculation of the nuclear excitation by electronic transition (NEET) rate is presented in a 201Hg plasma at local thermodynamic equilibrium. We also report on a new way of de-exciting isomeric states in plasma. This indirect decay mode is illustrated in the case of the 84Rb isomer nucleus.

Published
2011
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11. Observations of plasma heating by fast electron transport at the back side of solid targets

Author

V. Méot, G. Claverie, M. Gerbaux, F. Hannachi, V. T. Tikhonchuk, M. M. Aléonard, J. N. Scheurer, F. Gobet, Jérôme Breil, Ph. Nicolaï, Erik Brambrink, P. Audebert, J. J. Santos, G. Malka, M. Tarisien, P. Morel, 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), Laboratoire pour l'utilisation des lasers intenses (LULI), Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB)

Subjects
Materials science, General Physics and Astronomy, Plasma, Electron, Laser, 01 natural sciences, Electron transport chain, law.invention, Interferometry, law, Physics::Plasma Physics, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Physics::Space Physics, General Materials Science, Irradiation, Physical and Theoretical Chemistry, Atomic physics, 010306 general physics, Adiabatic process, Intensity (heat transfer)
Abstract

Fast adiabatic plasma heating of a thin solid target irradiated by a high intensity laser has been observed by optical fast interferometry diagnostic. It is driven by the hot electron current induced by the laser plasma interaction at the front side of the target. Radial and longitudinal temperature profiles are calculated to reproduce the observed rear side plasma expansion. The main parameters of the suprathermal electrons have been calculated from these observations.

Published
2009
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12. Effect of the plasma density scale length on the properties of Brehmsstrahlung X-ray sources created by picosecond laser pulses

Author

F. Hannachi, M. Gerbaux, J. N. Scheurer, M. M. Aléonard, M. Tarisien, A. Compant La Fontaine, A. Boscheron, J. Grenier, O. Landoas, F. Gobet, G. Lidove, Christian Courtois, Pierre Morel, Rachel Nuter, V. Méot, Erik Lefebvre, G. Malka, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre d'études scientifiques et techniques d'Aquitaine (CESTA), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), and 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)

Subjects
Physics, Silicon, business.industry, Bremsstrahlung, chemistry.chemical_element, Plasma, Semiconductor device, Condensed Matter Physics, 01 natural sciences, Electromagnetic radiation, 010305 fluids & plasmas, Optics, chemistry, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Plasma diagnostics, 010306 general physics, business, Beam (structure), Diode
Abstract

Results of an experimental study of multi-MeV bremsstrahlung x-ray sources created by picosecond laser pulses are presented. The x-ray source is created by focusing the short pulse in an expanding plasma obtained by heating a solid target with a time-delayed nanosecond laser beam. The high-energy part of the x-ray spectrum and emission lobe are inferred from photonuclear activation techniques. The x-ray dose is measured with silicon diodes. Two-dimensional images of the source are reconstructed from a penumbral imaging technique. These results indicate the creation of a relatively small source, below 200 µm diameter, delivering doses up to 12 mrad in air at 1 m with x-ray temperature up to 2.8 MeV. The diagnostics used give access to a whole set of coherent experimental results on the x-ray source properties which are compared to extensive numerical simulations. X-ray intensity and temperature are found to increase with the size of the preplasma. ©2009 American Institute of Physics

Published
2009
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13. Fast electron transport and induced heating in solid targets from rear side interferometry imaging

Author

Patrick Audebert, Vladimir Tikhonchuk, Erik Brambrink, V. Méot, M. Gerbaux, M. M. Aléonard, F. Hannachi, G. Claverie, K. U. Amthor, P. Morel, J. J. Santos, G. Malka, M. Tarisien, J. N. Scheurer, F. Gobet, Ph. Nicolaï, Jérôme Breil, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Centre d'Etudes Lasers Intenses et Applications (CELIA), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB), Laboratoire pour l'utilisation des lasers intenses (LULI), Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), and Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Plasma, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Laser, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, law.invention, Interferometry, Physics::Plasma Physics, law, Physics::Space Physics, 0103 physical sciences, Electron temperature, Plasma diagnostics, Irradiation, Atomic physics, 010306 general physics, Adiabatic process
Abstract

Fast adiabatic plasma heating of a thin solid target irradiated by a high intensity laser has been observed by an optical fast interferometry diagnostic. It is driven by the hot electron current induced by the laser plasma interaction at the front side of the target. Radial and longitudinal temperature profiles are calculated to reproduce the observed rear-side plasma expansion. The main parameters of the suprathermal electrons (number, temperature, and divergence) have been deduced from these observations.

Published
2008
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14. Particle characterisation for the evaluation of 181mTa excitation yield in millijoule laser induced plasmas

Author

M. Tarisien, R. Fedosejevs, J. N. Scheurer, F. Hannachi, F. Gobet, M. Gerbaux, Stéphane Petit, P. Morel, V. Méot, G. Malka, Fabien Dorchies, C. Fourment, M. M. Aléonard, G. Claverie, Dominique Descamps, 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), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB)

Subjects
Physics, 010308 nuclear & particles physics, Scattering, Electron, Plasma, Inelastic scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Condensed Matter Physics, Laser, 7. Clean energy, 01 natural sciences, Atomic and Molecular Physics, and Optics, Charged particle, law.invention, Ion, Photoexcitation, law, 0103 physical sciences, Atomic physics, 010306 general physics
Abstract

The particles (ions, atoms, x-rays and high-energy electrons) resulting from the interaction of a high repetition rate laser with a tantalum target are characterized at laser intensities ranging between 3 × 1015 and 6 × 1016 W cm-2 using plasma and nuclear physics techniques. A simple model is developed to estimate, from these data, the ^181 Ta isomeric state excitation yields in the ablated matter and in the remaining target. Both nuclear photoexcitation and electron inelastic scattering processes have been taken into account in the calculations. A maximum of a few 10-3 excitations per laser shot are predicted in the investigated intensity range.

Published
2008
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15. High flux of relativistic electrons produced in femtosecond laser-thin foil target interactions: characterization with nuclear techniques

Author

A. Guemnie-Tafo, P. Morel, M. M. Aléonard, M. Tarisien, M. Manclossi, Y. Glinec, M. Gerbaux, Jérôme Faure, F. Hannachi, G. Malka, V. Méot, G. Claverie, Victor Malka, J. N. Scheurer, F. Gobet, Joao Santos, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Département de Physique Théorique et Appliquée (DPTA), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and 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)

Subjects
Physics, Electron spectrometer, Spectrometer, Monte Carlo method, Electron, Plasma, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Laser, 01 natural sciences, 010305 fluids & plasmas, Characterization (materials science), law.invention, law, 0103 physical sciences, Femtosecond, Atomic physics, 010306 general physics, Instrumentation
Abstract

We present a protocol to characterize the high energy electron beam emitted in the interaction of an ultraintense laser with matter at intensities higher than 10(19) W cm(-2). The electron energies and angular distributions are determined as well as the total number of electrons produced above a 10 MeV threshold. This protocol is based on measurements with an electron spectrometer and nuclear activation techniques, combined with Monte Carlo simulations based on the GEANT3 code. The method is detailed and exemplified with data obtained with polypropylene and copper thin solid targets at a laser intensity of 2x10(19) W cm(-2). Special care is taken of the different sources of uncertainties. In particular, the reproducibility of the laser shots is considered.

Published
2008
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16. Effective photoexcitation cross section of115In(γ,γ′)115mIn from photoactivation data

Author

M-M. Aléonard, Pierre Morel, M. Tarisien, T. Bonnet, Marco Martini, D. Denis-Petit, M. Versteegen, F. Hannachi, V. Méot, Sophie Péru, F. Gobet, M. Comet, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and 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)

Subjects
Physics, Nuclear reaction, Range (particle radiation), 010308 nuclear & particles physics, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Bremsstrahlung, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Engineering physics, Electromagnetic radiation, Photoexcitation, Nuclear physics, Cross section (physics), Metastability, Excited state, 0103 physical sciences, 010306 general physics
Abstract

International audience; Photoexcitation yields of the ^115mIn metastable state were measured with Bremsstrahlung gamma beams over a range of endpoint energies between 4.5 and 18 MeV. An effective cross section of the ^115In(gamma,gamma')^115mIn photoexcitation cross section was determinedto reproduce the data. This cross section is built from a cross section calculated with the TALYS code, to which an enhancement is added at about 8.5 MeV.

Published
2016
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17. Energetic electrons produced in the interaction of a kiloHertz femtosecond laser with tantalum targets

Author

Robert Fedosejevs, P. Morel, M. Tarisien, F. Hannachi, V. Méot, C. Fourment, M. Gerbaux, F. Gobet, Stéphane Petit, G. Malka, J. N. Scheurer, Fabien Dorchies, G. Claverie, M. M. Aléonard, Dominique Descamps, 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), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, BPRS, 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), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB)

Subjects
Physics, Photon, Tantalum, Bremsstrahlung, chemistry.chemical_element, Electron, Plasma, Photon energy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Laser, 01 natural sciences, 7. Clean energy, Atomic and Molecular Physics, and Optics, 010305 fluids & plasmas, law.invention, chemistry, law, 0103 physical sciences, Femtosecond, Atomic physics, 010306 general physics
Abstract

The electrons produced in the interaction of a high repetition rate laser with a thick tantalum target generate a continuous distribution of photons via the bremsstrahlung process occurring mainly in the target. The photon energy distributions, between 50 and 500 keV, are unfolded to obtain the true X-ray energy distributions. These distributions are used in a Monte Carlo simulation to infer the initial electron energy distributions. These properties have been studied at laser intensities ranging from 3 × 1015 to 6 × 1016 W cm− 2. The electron energy distributions are different above ≃2 × 1016 W cm− 2 as compared to lower intensities. This is evidence for a different laser plasma interaction regime.

Published
2007
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18. Nuclear Physics with High-Intensity Lasers

Author

M. M. Aléonard, G. Malka, M. Tarisien, J. N. Scheurer, F. Gobet, F. Hannachi, M. Gerbaux, and G. Claverie

Subjects
Physics, Internal conversion, 010308 nuclear & particles physics, business.industry, 0103 physical sciences, High intensity lasers, Optoelectronics, 010306 general physics, business, 01 natural sciences
Published
2006
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19. Absolute energy distribution of hard X-rays poduced in the interaction of a kHz femtosecond laser with tantalum targets

Author

S. Petit, G. Claverie, F. Gobet, C. Fourment, B. Liesfeld, M. M. Aléonard, F. Hannachi, G. Malka, Dominique Descamps, M. Gerbaux, S. Hanvey, F. Blasco, J. N. Scheurer, J. F. Chemin, L. Robson, Robert Fedosejevs, P. Morel, Fabien Dorchies, M. Tarisien, V. Méot, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Centre d'Etudes Lasers Intenses et Applications (CELIA), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB), Service de Physique Nucléaire (SERVICE DE PHYSIQUE NUCLéAIRE), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Etudes Aérodynamiques (LEA), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Service d'Hématologie Clinique, Hôpital Schaffner, Department of Biomedical Science, University of Sheffield [Sheffield], 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), and Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Photon, plasma simulation, Physics::Instrumentation and Detectors, tantalum, Astrophysics::High Energy Astrophysical Phenomena, plasma light propagation, 01 natural sciences, Particle detector, 010305 fluids & plasmas, law.invention, Optics, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, high-speed optical techniques, 010306 general physics, Absorption (electromagnetic radiation), plasma production by laser, Instrumentation, ComputingMilieux_MISCELLANEOUS, 52.59.Px, 52.25.Os, 52.50.Jm, 52.70.Nc, 52.38.Ph, 52.65.Pp, [PHYS]Physics [physics], Physics, plasma diagnostics, business.industry, Compton scattering, Laser, Compton effect, Femtosecond, Scintillation counter, Plasma diagnostics, plasma X-ray sources, Atomic physics, business
Abstract

Previous reports have indicated the anomalous excitation rate for the 6.2 keV nuclear level of 181Ta in a plasma produced with a femtosecond laser. A detailed characterization of the electrons and x-ray sources produced in such a plasma is required to interpret these results. In a preliminary work, the continuous energy distribution of hard x rays 10–500 keV produced in the interaction of a kilohertz femtosecond laser beam with a tantalum solid target is investigated in the 31015–6 1016 W/cm2 range of intensity. A sodium iodide detector with appropriate shielding is used. Strong collimation and absorption filters are used to avoid the pileup of photons in the detector. The response function of this setup is calculated with the GEANT3 simulation code. We demonstrate the necessity to quantify the Compton scattered events in the raw spectra in order to restore the absolute x-ray energy distribution.

Published
2006
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20. Multi-MeV laser-produced particle sources: Characterization by activation techniques

Author

M. Gerbaux, J. J. Santos, A. Guemnie-Tafo, M. Tarisien, J. N. Scheurer, F. Gobet, Y. Glinec, F. Hannachi, M. Manclossi, V. Méot, G. Claverie, M. M. Aléonard, G. Malka, Victor Malka, Jérôme Faure, P. Morel, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and 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)

Subjects
Electron spectrometer, Proton, Chemistry, Bremsstrahlung, General Physics and Astronomy, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Laser, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, law.invention, Baryon, law, 0103 physical sciences, Atomic number, Atomic physics, 010306 general physics, Nucleon, Nuclear Experiment
Abstract

International audience; We present here results obtained in an experiment carried out using the CPA beam of the "Salle Jaune" laser system at Laboratoire d'Optique Appliquée (LOA). The generation of high energy electrons and protons escaping from the plasma has been investigated in the interaction of a 2 J, 30 fs laser with CH or metallic foils. The energy and angular distributions of the supra-thermal electrons produced with different targets are characterized by using both an electron spectrometer and bremsstrahlung induced ($\gamma $,n) reactions. We measured simultaneously the number of energetic protons produced using (p,n) reactions. A correlation between the electrons and the protons production is observed together with a dependence of the number of supra-thermal electrons on the atomic number of the target element.

Published
2006
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21. Search for nuclear excitation by electronic transition inU235

Author

P. Morel, F. Hannachi, M. M. Aléonard, V. Méot, G. Malka, J. N. Scheurer, J.F. Chemin, G. Claverie, M. R. Harston, and F. Gobet

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, 01 natural sciences, Molecular electronic transition, Full width at half maximum, Distribution (mathematics), 0103 physical sciences, Atom, Uranium-235, Atomic physics, 010306 general physics, Intensity (heat transfer), Energy (signal processing), Excitation
Abstract

We have searched for the nuclear excitation by electronic transition (NEET) of the isomeric level at 76 eV in $^{235}\mathrm{U}$ in a plasma induced by a YAG laser with an energy of 1 Joule and a full width at half maximum time distribution of 5 ns, operating at an intensity of ${10}^{13}\phantom{\rule{0.3em}{0ex}}\text{W}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}2}$. We present a thorough description of the experimental conditions and analysis of our data. In this experimental situation we do not detect any excitation of the isomeric level, a result that is at variance with a previously reported one. An upper limit of $6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ per atom and per second averaged over the laser-pulse width has been set on the nuclear excitation rate. This value is compared with results obtained in previous experimental and theoretical works.

Published
2004
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22. The VXI electronics of the DIAMANT particle detector array

Author

J.F. Chemin, J. N. Scheurer, G. Hegyesi, J. L. Pedroza, Jozsef Molnar, V. F. E. Pucknell, B. M. Nyakó, K. Juhász, J. Gál, Gábor Kalinka, and M. M. Aléonard

Subjects
Physics, Nuclear and High Energy Physics, Signal processing, Spectrometer, business.industry, Detector, Constant fraction discriminator, Zero crossing, Particle detector, Charged particle, Optics, Figure of merit, business, Instrumentation
Abstract

A VXI card designed for the processing of signals from the particle detector array DIAMANT, a CsI(Tl) light charged particle ancillary detector system to the EUROBALL and the EXOGAM gamma-spectrometers, is described. The card provides particle energy, particle-type and time-reference information and is compatible with the existing signal-processing system of EUROBALL/EXOGAM. In order to have full compatibility with the electronics of these spectrometers without sacrificing the performance of the card, some new solutions are used in the signal processing. For particle discrimination three methods can be selected; the ballistic deficit method, the zero-crossing method and a combination of these two methods. The figure of merit of the particle discrimination using the combined method is better than that of the zero crossing or the ballistic deficit method individually. Timing signals for particle–gamma coincidence are derived by a specially designed non-delay-line constant fraction discriminator, which exhibits low rise-time-dependent walk. The card has been tested with EUROBALL. The results of these tests are presented.

Published
2004

23. Correction method for Doppler broadened $\gamma$-ray lines using the linear momentum of the evaporated charged particles in heavy-ion induced fusion-evaporation reactions

Author

Emanuele Vardaci, G. Barreau, J. N. Scheurer, M. Harston, A. Brondi, G. La Rana, D. Cabaussel, F. Hannachi, R. Moro, F. Bourgine, M. M. Aléonard, J.F. Chemin, D. Boivin, M. Aiche, D. Curien, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), 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), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), 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), EUROBALL, M., Aiche, M. M., Alonard, G., Barreau, D., Boivin, F., Bourgine, D., Cabaussel, J. F., Chemin, M., Harston, J. N., Scheurer, LA RANA, Giovanni, Moro, RENATA EMILIA MARIA, Brondi, Augusto, Vardaci, Emanuele, and D. CURIEN, F. HANNACHI

Subjects
Nuclear and High Energy Physics, Light charged particle, Fusion–evaporation, Astrophysics::High Energy Astrophysical Phenomena, EUROBALL SPECTROMETER, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 7. Clean energy, SUPERDEFORMED BAND, Coincidence, DIAMANT, symbols.namesake, GAMMASPHERE, 0103 physical sciences, Doppler shift, Nuclear Experiment, 010306 general physics, COMPOUND NUCLEUS, GAMMA SPECTROSCOPY, Instrumentation, DETECTOR, Physics, Fusion, Spectrometer, 010308 nuclear & particles physics, Detector, Evaporation (deposition), Charged particle, EUROGAM II, symbols, Granularity, Atomic physics, Doppler effect
Abstract

A method based on the conservation of linear momentum is used to correct the position and the width of the γ-ray lines of the residual nucleus produced in heavy-ion induced fusion–evaporation reactions. This method implies the measurement of the total number of the emitted particles, their masses, energies and directions of emission in coincidence with the prompt γ-rays. It has been applied to the 120 MeV 32 S + 58 Ni reaction whose data have been collected using the high efficiency and large granularity 4π light charged particle detector DIAMANT, coupled to the 4π γ-ray spectrometer EUROGAM II.

Published
2003
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24. Electron Acceleration by a Wake Field Forced by an Intense Ultrashort Laser Pulse

Author

M. Pittman, Frédéric Burgy, J. N. Scheurer, B. Walton, M. M. Aléonard, J. F. Chemin, Victor Malka, Erik Lefebvre, G. Malka, Stuart Mangles, Jean-Paul Chambaret, Karl Krushelnick, Sven Fritzler, A. E. Dangor, Jean-Philippe Rousseau, Zulfikar Najmudin, Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Théorique et Appliquée (DPTA), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Blackett Laboratory, Imperial College London, and 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)

Subjects
Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multidisciplinary, business.industry, Pulse duration, Particle accelerator, Plasma, Electron, Laser, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, Pulse (physics), law.invention, Optics, Relativistic plasma, law, Physics::Plasma Physics, Electric field, 0103 physical sciences, Atomic physics, 010306 general physics, business, Computer Science::Databases
Abstract

International audience; Plasmas are an attractive medium for the next generation of particle accelerators because they can support electric fields greater than several hundred gigavolts per meter. These accelerating fields are generated by relativistic plasma waves--space-charge oscillations--that can be excited when a high-intensity laser propagates through a plasma. Large currents of background electrons can then be trapped and subsequently accelerated by these relativistic waves. In the forced laser wake field regime, where the laser pulse length is of the order of the plasma wavelength, we show that a gain in maximum electron energy of up to 200 megaelectronvolts can be achieved, along with an improvement in the quality of the ultrashort electron beam.

Published
2002
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25. Relativistic electron generation in interactions of a 30 TW laser pulse with a thin foil target

Author

M. M. Aléonard, Sven Fritzler, N. Cochet, G. Grillon, G. Malka, G. Claverie, Erik Lefebvre, S. Moustaizis, Victor Malka, J. N. Scheurer, M. Harston, Vladimir Tikhonchuk, J. F. Chemin, Philippe Balcou, L. Notebaert, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), and Chambon, Pascale

Subjects
Physics, Gamma ray, Bremsstrahlung, Photofission, Electron, Laser, Electron spectroscopy, Electromagnetic radiation, law.invention, law, [PHYS.PHYS.PHYS-INS-DET] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Cathode ray, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Atomic physics
Abstract

Energy and angular distributions of the fast outgoing electron beam induced by the interaction of a 1 J, 30 fs, 2 x 10(19) W/cm(2), 10 Hz laser with a thin foil target are characterized by electron energy spectroscopy and photonuclear reactions. We have investigated the effect of the target thickness and the intensity contrast ratio level on the electron production. Using a 6-microm polyethylene target, up to 4 x 10(8) electrons with energies between 5 and 60 MeV were produced per laser pulse and converted to gamma rays by bremsstrahlung in a Ta secondary target. The rates of photofission of U as well as photonuclear reactions in Cu, Au, and C samples have been measured. In optimal focusing conditions, about 0.06% of the laser energy has been converted to outgoing electrons with energies above 5 MeV. Such electrons leave the target in the laser direction with an opening angle of 2.5 degrees.

Published
2002

26. Optimizing photonuclear reactions with a high-intensity laser

Author

P. Balcou, V. T. Tikhonchuk, G. Claverie, Stavros D. Moustaizis, G. Malka, Sven Fritzler, J. N. Scheurer, M. Pittman, Erik Lefebvre, Victor Malka, G. Grillon, M. M. Aléonard, M. R. Harston, L. Notebaert, and J. F. Chemin

Subjects
Nuclear reaction, Physics, Tantalum, Bremsstrahlung, chemistry.chemical_element, Electron, Laser, law.invention, chemistry, law, Atomic physics, Spectroscopy, Intensity (heat transfer), Excitation
Abstract

Photo-excitation nuclear reactions induced by the 2J, 30 fs, 4x1010W/cm2, 10 Hz LOA laser were optimized with respect to the thickness of the solid target. Using 6 micrometers CH targets, electrons up to 60 MeV have been produced and converted to (gamma) -rays by Bremsstrahlung in a Ta piece. The rate of photo-fission of 238U, as well as photo- excitation nuclear reactions in Cu, Au and C samples have been measured. More than 106 nuclear reactions were obtained after 60 subsequent laser shots. The high energy electrons are forward focused, within 15 degree(s), as observed from the angular distribution of the activation in Cu. 1% of laser energy was converted to (gamma) -rays with energies higher than 10 MeV.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Published
2001
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27. Resonant nuclear excitation with high-energy lasers

Author

J. N. Scheurer, J. F. Chemin, V. Méot, G. Claverie, G. Malka, M. M. Aléonard, and M. R. Harston

Subjects
Internal conversion, Chemistry, Atomic electron transition, Excited state, Atom, Bound state, Electron, Atomic physics, Transition rate matrix, Excitation
Abstract

A search of Nuclear Excitation by Electron Transition (NEET) in 235 U excited in the plasma produced by a 300 mJ, 10 ns laser is presented. Many experimental aspects have been faced to evidence the low rate of NEET excitation of the 76 eV isomeric level in 235 U with a plasma temperature T=25 eV. The experimental limit measured for the transition rate for the 76 eV 235 U m state is N < 2. 10 -5 s -1 . Several potential upgrades are considered to aim at a measure of the NEET excitation rate in 235 U. 1. INTRODUCTION The Nuclear Excitation by Electron Transition (NEET) process is the excitation of the nucleus with simultaneous deexcitation of the atomic system in the same atom [1]. This process is just the reverse of the BIC (for Bound Internal Conversion) in which the deexcitation energy of the nucleus is transferred, via a virtual photon, to the excitation of an atomic electron from one bound state to another bound state. The BIC has been recently studied experimentally and theoretically in

Published
2001
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28. High-spin states in155Er

Author

N. Nica, G. Duchêne, V. E. Iacob, J. Dudek, F. A. Beck, Th. Byrski, D. Curien, G. de France, B. Haas, B. Kharraja, D. Prévost, C. Petrache, H. Savajols, J. P. Vivien, L. Han, K. Zuber, M. Aïche, M. M. Aléonard, J. F. Chemin, C. W. Beausang, S. Clarke, P. J. Dagnall, M. Smith, P. J. Twin, J. Simpson, and M. A. Bentley

Subjects
Physics, Nuclear and High Energy Physics, Decay scheme, Proton, Spin states, Quadrupole, Order (ring theory), Neutron, Atomic physics, Energy (signal processing), Spin-½
Abstract

The high-spin decay scheme of ${}^{155}\mathrm{Er},$ known previously, has been considerably extended by using the EUROGAM II \ensuremath{\gamma}-ray array. The so-called quasi-isotropic gating data-analysis method, capable of providing spin and parity assignments with triple or quadruple coincidence data has been used. With such coincidence information, we have determined \ensuremath{\gamma}-ray angular distributions, DCO ratios, and linear polarizations for many of the observed transitions. The level scheme is interpreted by using the particle-hole analysis based on the deformed Woods-Saxon potential and the monopole pairing interaction. The results indicate that at $\ensuremath{\sim}12.3$ MeV excitation energy, all nine valence particles around the ${}_{64}^{146}{\mathrm{Gd}}_{82}$ core exhaust the maximum spin of $I=79/2\ensuremath{\Elzxh}.$ At higher spin, relatively high-energy transitions, of the order of $\ensuremath{\sim}1.5$ MeV, related to the breaking of the proton or neutron cores are observed. According to the calculations, this corresponds to an oblate-shape polarization of the nucleus with quadrupole deformation ${\ensuremath{\beta}}_{2}\ensuremath{\sim}\ensuremath{-}0.12.$

Published
2001
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29. γ-ray studies of the fission of [sup 238]U induced by [sup 12]C, spectroscopy and fission dynamics

Author

W. Korten, Ch. Theisen, M. Aiche, Th. Ethvignot, G. Barreau, I. Deloncle, A. Astier, N. Redon, John Durell, J. N. Scheurer, W.R. Phillips, Stephane Perries, T.P. Doan, Y. Le Coz, D. Grimwood, M. M. Aléonard, A. G. Smith, V. Méot, R. Lucas, B. J. Varley, M. G. Porquet, J.F. Chemin, M. Houry, A. Roach, and G. Belier

Subjects
Nuclear reaction, Nuclear physics, Fission products, Cluster decay, Fission, Chemistry, Nuclear Theory, Physics::Atomic and Molecular Clusters, Gamma ray, Neutron, Nuclear Experiment, Semiconductor detector, Spontaneous fission
Abstract

Fission studies have been known for a long time to provide neutron-rich nuclei in various states of excitation energy, spin and deformation. Although many studies have been performed concerning fission fragments from spontaneous fission and neutron induced fission, a renewed interest in fission-fragment spectroscopy has occurred with the elaboration of large Ge detector arrays such as EUROBALL. We have recently performed an experiment with EUROBALL III using SAPhIR; a fission-fragment detector made from photovoltaic cells. The compact and versatile geometry of SAPhIR allows it to be installed inside the γ-ray detector, and to obtain additional information from the fission process as well as a timing reference. Neutron-rich nuclei have been populated in the fusion-fission reaction 238U+12C leading to the compound nucleus 250Cf. First results of this experiment are presented.

Published
1998
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30. Octupole Vibrations of the Superdeformed $^{196}$Pb Nucleus

Author

W. Korten, M. M. Aléonard, Josette Duprat, H. Sergolle, N. Dozié, S. Baldsiefen, C. W. Beausang, H. Hübel, D. Curien, Ch. Bourgeois, J.F. Sharpey-Schafer, U. J. van Severen, Mohammed Kaci, A. Astier, Laurent Ducroux, B. J. P. Gall, S. Bouneau, F. Azaiez, N. Redon, Takashi Nakatsukasa, I. Deloncle, Matthias Meyer, M. G. Porquet, F.A. Beck, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), 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), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, Yrast, Nuclear Theory, Hadron, Phase (waves), General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], medicine.anatomical_structure, Excited state, medicine, Atomic physics, Nuclear Experiment, Spin (physics), Nucleus, Excitation
Abstract

The study of the superdeformed (SD)196Pb nucleus has been revisited using the Eurogam Phase 2 spectrometer. All of the three observed excited SD bands were found to decay to the yrast SD band through, presumably,E1 transitions, allowing relative spin and excitation energy assignments. Comparisons with calculations using the random-phase approximation suggest that all three excited bands can be interpreted as octupole vibrational structures.

Published
1997

31. First results with DIAMANT and EUROGAM

Author

J.P. Goudour, A. Brondi, Emanuele Vardaci, R. Moro, J. N. Scheurer, M. Harston, F. Bourgine, J.F. Chemin, M. Aiche, G. La Rana, D. Cabaussel-Sellam, D. Curien, G. Barreau, M. M. Aléonard, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), 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), EUROGAM, Chambon, Pascale, M., Aiche, M. M., Aleonard, G., Barreau, F., Bourgine, Brondi, Augusto, D., Cabausselsellam, D., Curien, J. F., Chemin, J. P., Goudour, M., Harston, LA RANA, Giovanni, Moro, RENATA EMILIA MARIA, J. N., Scheurer, and Vardaci, Emanuele

Subjects
Physics, Coupling, LIGHT CHARGED PARTICLE ARRAY, Nuclear and High Energy Physics, Fusion, 010308 nuclear & particles physics, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], Detector, Evaporation, EUROGAM, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, DIAMANT, Charged particle, Nuclear physics, symbols.namesake, 0103 physical sciences, symbols, Nuclear fusion, Particle, Atomic physics, Nuclear Experiment, 010306 general physics, Doppler effect
Abstract

The coupling of efficient particle and gamma detection arrays is a powerful tool to study the deexcitation of both compound and residual nuclei in fusion evaporation reactions. We show first results obtained coupling the DIAMANT (4 pi light charged particle array) and EUROGAM (4 pi gamma array) detectors demonstrating the improvement in the resolving power by this combination. For gamma rays of similar or equal to 800keV improvements in the Doppler correction up to 50% have been reached for the 2 alpha exit channel following the fusion of S-32+Ni-58 at 120 MeV bombarding energy (beta similar or equal to 3%).

Published
1997

32. DIAMANT and EUROGAM : improvements in the observation limits and study of the ^{90}Ru and ^{44}Ti compound nuclei decay

Author

M. M. Aléonard, J.F. Chemin, F. Bourgine, D. Cabaussel, Emanuele Vardaci, J. N. Scheurer, M. Harston, G. Barreau, D. Curien, G. La Rana, R. Moro, A. Brondi, M. Aiche, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), 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), Faessler A., M. M., Aleonard, M., Aiche, G., Barreau, F., Bourgine, D., Cabaussel, J. F., Chemin, M., Harston, J. N., Scheurer, Brondi, Augusto, LA RANA, Giovanni, Moro, RENATA EMILIA MARIA, Vardaci, Emanuele, D., Curien, and Chambon, Pascale

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, LIGHT CHARGED PARTICLE DETECTORS, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], 010308 nuclear & particles physics, 0103 physical sciences, EUROGAM, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010306 general physics, 01 natural sciences, DIAMANT
Published
1996

33. The Eurogam project : status and developments

Author

M. M. Aléonard and Chambon, Pascale

Subjects
Unix, Engineering, Workstation, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], business.industry, Detector, Electrical engineering, Particle detector, Whole systems, law.invention, Upgrade, Data acquisition, law, business, Computer hardware
Abstract

The features of the EUROGAM multidetector array, composed of 45 Ge with their associated anti‐Compton shield are presented. The properties of the detectors and an upgrade of the geometry are described. The data acquisition system incorporates integrated electronic designed with the new VXI standard; the whole system is distributed on a network and takes benefit of UNIX based workstations and the real time facilities of VxWorks.

Published
1991

34. A 4π light charged particle multidetector for reaction channel identification and discrimination

Author

F. Azaiez, G. Claverie, M. M. Aléonard, J. N. Scheurer, F.A. Beck, G. Costa, S. Andriamonje, and J.F. Chemin

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Channel (digital image), Physics::Instrumentation and Detectors, Detector, Scintillator, Atomic physics, Nuclear Experiment, Instrumentation, Charged particle
Abstract

We describe a compact 4π multidetector system to detect light charged particles emitted in a fusion-evaporation nuclear reaction. It consists of 17 fast plastic scintillators closely assembled in a cubic arrangement. The detector can be enclosed in the French gamma multidetector facility: the “chateau de cristal”. The characteristics and the performance of this multidetector are discussed from the 58 Ni + 54 Fe fusion-evaporation reaction.

Published
1989
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35. Structure of neutron rich palladium isotopes produced in heavy ion induced fission

Author

M. M. Aléonard, Stephane Perries, Y. Le Coz, John Durell, M. G. Porquet, B. J. Varley, J.F. Chemin, I. Deloncle, G. Barreau, Ch. Theisen, R. Lucas, M. J. Leddy, M. Aiche, N. Redon, A. Astier, A. G. Smith, F. Becker, M. Houry, A. Roach, K. Hauschild, J. N. Scheurer, Michel Girod, T.P. Doan, W. Korten, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), 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), Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Fission, Computer Science::Information Retrieval, Nuclear Theory, Hadron, chemistry.chemical_element, Computer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Coincidence, chemistry, Isotopes of palladium, 0103 physical sciences, Nuclear fusion, Neutron, Deformation (engineering), Atomic physics, Nuclear Experiment, 010306 general physics, Palladium, Nuclear Physics
Abstract

Kernel methods have recently been introduced to solve Natural Language Processing and Text Mining problems. Kernels define a generalised similarity measure between objects of arbitrary structure, with three interesting properties, namely the ability to incorporate prior knowledge about the problem, the implicit mapping of the data into a new feature space, which allows for very richer representation and where problem solving is easier, and finally the independence of learning algorithms from the dimension of this new feature space (—the Kernel trick“). These properties, coupled with robust learning algorithms (for classification, clustering, dimension reduction, filtering, ...) provide some remarkable results in Text Mining tasks, such as document categorization, concept clustering, word sense disambiguation, information extraction, relationship extraction and automatic multilingual lexicon extraction.

36. Electron acceleration beyond 200 MeV in underdense plasmas using table top laser systems

Author

A. E. Dangor, Erik Lefebvre, Zulfikar Najmudin, M. M. Aléonard, Jean-Paul Chambaret, J.P. Rousseau, B. Walton, Sven Fritzler, Frédéric Burgy, J. F. Chemin, J. N. Scheurer, Stuart Mangles, Victor Malka, G. Malka, and Karl Krushelnick

Subjects
Physics, Electron density, business.industry, Plasma, Laser, Beam parameter product, Intensity (physics), law.invention, Acceleration, Optics, Physics::Plasma Physics, law, Cathode ray, Physics::Accelerator Physics, Laser beam quality, Atomic physics, business
Abstract

In this article we present electron acceleration by the interaction of a multi‐TW, high repetition rate, table top laser at moderate intensity with an underdense plasma. We optimized this unique electron source in terms of the energy as well as the quality of the generated electron beam. The plasma period was chosen to be of the order of the laser pulse duration by adapting the plasma electron density. The waist of the laser focal spot was chosen to be larger than typical for comparable experiments. As a result, a very energetic, well‐collimated, and bright electron beam was generated, which has the highest energy ever produced by laser‐plasma interactions.

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