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Numerical investigation of spallation neutrons generated from petawatt-scale laser-driven proton beams

Matter and Radiation at Extremes 2022年第2期7卷 8-17页

作者： B.Martinez S.N.Chen S.Bolaños N.Blanchot G.Boutoux W.Cayzac C.Courtois X.Davoine A.Duval V.Horny I.Lantuejoul L.Le Deroff P.E.Masson-Laborde G.Sary B.Vauzour R.Smets L.Gremillet J.Fuchs LULI-CNRS CEAUPMC Univ Paris 06:Sorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance CEA DAMDIFF-91297 ArpajonFrance Horia Hulubei National Institute of Physics and Nuclear Engineering Bucharest-MagureleRomania CEA DAMCESTAF-33114 Le BarpFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChâtelFrance lpp Sorbonne UniversitéCNRSEcole PolytechniqueF-91128 Palaiseau CedexFrance

Laser-driven neutron sources could offer a promising alternative to those based on conventional accelerator technologies in delivering compact beams of high brightness and short duration.We examine this through particle-in-cell and Monte Carlo simulations that model,respectively,the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary lead targets.Laser parameters relevant to the 0.5 PW LMJ-PETAL and 0.6–6 PW Apollon systems are considered.Owing to its high intensity,the 20-fs-duration 0.6 PW Apollon laser is expected to accelerate protons up to above 100MeV,thereby unlocking efficient neutron generation via spallation reactions.As a result,despite a 30-fold lower pulse energy than the LMJ-PETAL laser,the 0.6 PW Apollon laser should perform comparably well both in terms of neutron yield and flux.Notably,we predict that very compact neutron pulses,of∼10 ps duration and∼100μm spot size,can be released provided the lead convertor target is thin enough(∼100μm).These sources are characterized by extreme fluxes,of the order of 10^(23) n cm^(−2) s^(−1),and even ten times higher when using the 6 PW Apollon laser.Such values surpass those currently achievable at large-scale accelerator-based neutron sources(∼10^(16) n cm^(−2) s^(−1)),or reported from previous laser experiments using low-Z converters(∼10^(18) n cm^(−2) s^(−1)).By showing that such laser systems can produce neutron pulses significantly brighter than existing sources,our findings open a path toward attractive novel applications,such as flash neutron radiography and laboratory studies of heavy-ion nucleosynthesis.

关键词： thereby attractive extreme

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The International Research Group in Geophysics Europe Africa： A Laboratory without Borders in the Earth Science and Environment

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Journal of Life Sciences 2012年第3期6卷 335-341页

作者： Christine Amory-Mazaudier lpp/UPMC/Polytechnique/CNRS 4 Avenue de Neptune 94107 Saint-Maur-des-Fossds France

It was in 1995 that, at the end of the international project IEEY (International Equatorial Electrojet Year), African and European scientists decided to create the IRGGEA (International Group in Geophysics Europe Africa) in order to pursue the scientific work started during the IEEY project. The main objective of IRGGEA was to introduce new fields of research in Africa and built teams of African scientists recognized at an international level in these new fields. To reach this goal, we developed days after days methods to manage smoothly a large network of scientists from developed and developing countries. After a short introduction on the field of research developed in the IRGGEA, we present the organization of the work based on sharing practices and the results obtained in terms of scientific publications and socio-cultural aspects as the increase of the number of women and positions for students in their countries. Such an experience is easy to reproduce.

关键词：地球科学地球物理环境实验室国际非洲欧洲国界发展中国家

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lpp1码与邮政快递

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中国自动识别技术 2013年第1期 71-74页

作者：边隆祥边信祥徐惠芳 lpp1码研发小组

自动分拣系统是判别一个国家快递自动化水平的一个重要标准。在国际快递业先进的国家，邮包标签主要用于快递自动分拣系统的自动识别，所以它必须要提供便于机器自动识别的符号（通常称其为条码）。物联网系统的发展对邮包有效信息量提... 详细信息

自动分拣系统是判别一个国家快递自动化水平的一个重要标准。在国际快递业先进的国家，邮包标签主要用于快递自动分拣系统的自动识别，所以它必须要提供便于机器自动识别的符号（通常称其为条码）。物联网系统的发展对邮包有效信息量提出越来越多的要求，所以现代先进的快递标签一般都同时拥有二类条码（一维条码和二维条码）。自动分拣系统的识别成功率取决于很多因素，如摄像系统、光源状况、环境干扰、标签污染、损坏等，所以任何快递自动分拣系统的识别成功率都不可能是100％。

关键词：自动分拣系统自动识别邮政二维条码自动化水平联网系统一维条码摄像系统

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Investigation of electron beam effects on L-shell Mo plasma produced by a compact LC generator using pattern recognition

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Matter and Radiation at Extremes 2019年第2期4卷 52-58页

作者： M.F.Yilmaz Y.Danisman M.Ozdemir B.Karlık J.Larour Basic Sciences Engineering DepartmentImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Mathematics and Computer Sciences Queensborough Community CollegeCUNYBaysideNew York 11364USA Neurosurgical Simulation Research and Training Centre Department of NeurosurgeryMontreal Neurological Institute and HospitalMcGill UniversityMontrealQuebec H3A 2B4Canada Laboratoire de Physique des Plasmas(lpp) Ecole PolytechniqueUPMCCNRSPalaiseauFrance

In this paper,the effects of an electron beam on X-pinch-produced spectra of L-shellMoplasma are investigated for the first time by principal component analysis(PCA);this analysis is compared with that of line ratio diagnostics.A spectral database for PCA extraction is arranged using a non-Local Thermodynamic Equilibrium(non-LTE)collisional radiative L-shell Mo model.PC vector spectra of L-shell Mo,including F,Ne,Na and Mg-like transitions are studied to investigate the polarization types of these transitions.PC1 vector spectra of F,Ne,Na and Mg-like transitions result in linear polarization of Stokes Q profiles.Besides,PC2 vector spectra show linear polarization of Stokes U profiles of 2p^(5)3s of Ne-like transitions which are known as responsive to a magnetic field[Trabert,Beiersdorfer,and Crespo Lo´pez-Urrutia,Nucl.InstrumMethods Phys.Res.,Sect.B 408,107–109(2017)].A 3D representation of PCA coefficients demonstrates that addition of an electron beam to the non-LTE model generates quantized,collective clusters which are translations of each other that follow V-shaped cascade trajectories,except for the case f=0.0.The extracted principal coefficients are used as a database for an Artificial Neural Network(ANN)to estimate the plasma electron temperature,density and beam fractions of the time-integrated,spatially resolved L-shellMoX-pinch plasma spectrum.PCA-based ANNs provide an advantage in reducing the network topology,with a more efficient backpropagation supervised learning algorithm.The modeled plasma electron temperature is about Te;660 eV and density n_(e)=1×10^(20) cm^(-3),in the presence of the fraction of the beams with f-0.1 and centered energy of 5 keV.

关键词： spectrum. beam transitions

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邮政的客户期望

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邮政研究 2004年第3期20卷 40-41页

作者：马莉.S.艾科诺西德里.奥斯丁伍德方芬 lpp国际法律事务所

文章介绍了邮政客户对邮政各方面的期望。

关键词：客户期望服务质量邮政改革世界邮政客户需求

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Meta-analysis of CO_(2) conversion,energy efficiency,and other performance data of plasma-catalysis reactors with the open access PIONEER database

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Journal of Energy Chemistry 2023年第11期86卷 318-342,I0007页

作者： Antoine Salden Maik Budde Carolina A.Garcia-Soto Omar Biondo Jairo Barauna Marzia Faedda Beatrice Musig ChloéFromentin Minh Nguyen-Quang Harry Philpott Golshid Hasrack Domenico Aceto Yuxiang Cai Federico Azzolina Jury Annemie Bogaerts Patrick Da Costa Richard Engeln María Elena Gálvez Timo Gans Tomas Garcia Vasco Guerra Carlos Henriques Monika Motak Maria Victoria Navarro Vasile I.Parvulescu Gerard Van Rooij Bogdan Samojeden Ana Sobota Paolo Tosi Xin Tu Olivier Guaitella Department of Physics University of Trento38100 PovoItaly Department of Applied Physics and Science Education Eindhoven University of Technology5600 MB EindhovenThe Netherlands Instituto de Plasmas e Fusão Nuclear Instituto Superior TécnicoUniversidade de Lisboa1049-001 LisboaPortugal lpp CNRSÉcole PolytechniqueSorbonne UniversitéUniversitéParis-SaclayIP-Paris 91128 PalaiseauFrance Department of Organic Chemistry Biochemistry and CatalysisUniversity of BucharestBucharestRomania Research Group PLASMANT Department of ChemistryUniversity of AntwerpUniversiteitsplein 1Wilrijk B-2610Belgium DIFFER 5612AJ EindhovenThe Netherlands Instituto de Carboquímica ICB-CSIC Zaragoza 50018Spain Faculty of Energy and Fuels AGH University of KrakowKrakowPoland Institut Jean le Rond d’Alembert CNRS UMR 7190-Sorbonne UniversitéSaint-Cyr l’Ecole 78210France Laboratoire Catalyse et Spectrochimie(LCS) CNRS-ENSICAEN-Universitéde Caen6 boulevard du Maréchal-Juin14000 CaenFrance CQE Centro de Química EstruturalInstituto Superior TécnicoUniversidade de LisboaAv.Rovisco Pais1049-001 LisboaPortugal School of Physical Sciences and National Centre for Plasma Science and Technology Faculty of Science and HealthDublin City UniversityDublinIreland ASML De Run 65015504 DR VeldhovenThe Netherlands Faculty of Science and Engineering Maastricht University6229 GS MaastrichtThe Netherlands CNR Istituto per la Scienza e Tecnologia dei Plasmi(ISTP)Italy Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been developed a

关键词： Open-access database on plasma-catalysis experiment CO_(2) conversion Plasma-catalysis Carbon capture and utilisation(CCU) Energy efficiency Specific energy input Dielectric barrier discharge Packed bed reactor Methanation Dry reforming of methane

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Solar Activity, Solar Wind and Geomagnetic Signatures

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Atmospheric and Climate Sciences 2013年第4期3卷 610-617页

作者： Jean-Louis Zerbo Frédéric Ouattara Christine Amory Mazaudier Jean-Pierre Legrand John D. Richardson Ecole Normale Supérieure de l’Université de Koudougou Koudougou Burkina Faso Institut National des Sciences de l’Univers (INSU) Paris France Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology Cambridge USA lpp-Laboratoire de Physique des Plasmas/UPMC/Polytechnique/CNRS Saint-Maur-des-Fossés France Université Polytechnique de Bobo-Dioulasso Bobo-Dioulasso Burkina Faso

The present study investigates solar events through geomagnetic activity and physical processes on the Sun: 1) Quiet activity (QA) related to the slow solar wind, 2) Recurrent activity (RA) related to high and moderate speed solar wind streams from coronal holes, 3) Shock activity (SA) identified by observations of SSCs and 4) Unclear activity (UA) which contains all activity not covered by the first three cases. For recent cycles, we analyze and emphasize some important results: Quiet activity is predominant for cycle 23, comprising 40% of the total activity and over 80% of the activity near solar minimum. Shock and recurrent activity contributions to total geomagnetic activity are largest in cycle 20. The most fluctuating events are observed during cycles 21 and 22. Throughout solar cycle 23, the contribution, from each type of activity, differs from recent solar cycles, with larger percentages of quiet and recurrent activity and less unclear activity. These percentages are similar to those in solar cycles observed in the late 1800s. Since 1963, solar wind data are available. We analyze the distribution of the solar wind velocity for each geomagnetic class of activity and find that: 1) Within each activity type aa does not depend on V, 2) Approximately 80% of the solar wind has V 450 km/s for RA, 3) SA and UA both have 60% of the solar wind V > 450 km/s. We found the following conditions for all four solar cycles: 1) For QA 95% of solar wind speeds are in the range 399 ± 69 km/s, 2) For RA 95% of the solar wind speeds range from 582 ± 110 km/s, 3) For SA 95% of the solar wind velocities are order of 482 ± 101.4 km/s, and 4) For UA 95% of solar wind speeds are 480 ± 85.82 km/s. These results confirm the classification scheme that QA reflects slow wind effects, RA effects high wind stream and UA answers to the fluctuations between high wind stream (~60%) and slow wind (~40%). The study shows that high wind stream (~60%) and slow wind (~40%) are both registered f

关键词： Solar Wind Geomagnetic Activity Solar Activity Geomagnetic Index aa

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