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Nuclear Science and Techniques 2022年第3期33卷 113-125页

作者： Xiao-Wen Zhu Claude Marchand Olivier Piquet Michel Desmons irfu CEAUniversite´Paris-Saclay91191 Gif-sur-YvetteFrance

Compact accelerator-based neutron source facilities are garnering attention and play an important and expanding role in material and engineering sciences,as well as in neutron science education and training.Neutrons are produced by bombarding a low-energy proton beam onto a beryllium or lithium target.In such an acceleratorbased neutron source,a radio frequency quadrupole(RFQ)is usually utilized to accelerate a high-intensity proton beam to a few MeV.This study mainly covers the highfrequency structure design optimizations of a 4-vane RFQ with pi-mode stabilizer loops(PISLs)and its RF stability analysis.A 176 MHz RFQ accelerator is designed to operate at a 10%duty factor and could accelerate an80 mA proton beam from 65 keV to 2.5 MeV within a length of 5.3 m.The adoption of PISLs ensures high RF stability,eases the operation of the accelerator,and implies less stringent alignment and machining tolerances.

关键词： Accelerator-based neutron source 4-vane RFQ accelerator Pi-mode stabilizer loops Perturbative analysis Electromagnetic design Multipacting simulation

Dynamics of strong and radiative decays of D_s-mesons in the hadrogenesis conjecture

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Chinese Physics C 2010年第9期34卷 1320-1323页

作者： M.Soyeur M.F.M.Lutz irfu/SPhN CEA/Saclay GSI Planckstrasse 1

The positive parity scalar D ＊ s0 （2317） and axial-vector D ＊ s1 （2460） charmed strange mesons are generated by coupled-channel dynamics through the s-wave scattering of Goldstone bosons off the pseudoscalar and vector D（D s ）-meson ground states.The specific masses of these states are obtained as a consequence of the attraction arising from the Weinberg-Tomozawa interaction in the chiral Lagrangian.Chiral corrections to order Q 2 χ are calculated and found to be small.The D ＊ s0 （2317） and D ＊ s1 （2460） mesons decay either strongly into the isospin-violating π 0 D s and π 0 D ？ s channels or electromagnetically.We show that the π 0-η and （K^ 0 D ^＋-K^ ＋ D^ 0 ） mixings act constructively to generate strong widths of the order of 140 keV and emphasize the sensitivity of this value to the KD component of the states.The one-loop contribution to the radiative decay amplitudes of scalar and axial-vector states is calculated using the electromagnetic Lagrangian to chiral order Q 2 χ .We show the importance of taking into account processes involving light vector mesons explicitly in the dynamics of electromagnetic decays.The radiative width are sensitive to both η D s and KD components,hence providing information complementary to the strong widths on the positive parity D s-meson structure.

关键词： charmed mesons D＊s0 （2317） D＊s1 （2460）

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中子的内部结构:来自BESIII的研究

Science Bulletin 2022年第6期67卷 557-560页

作者： Simone Pacetti Rinaldo Baldini Ferroli Andrea Bianconi Egle Tomasi-Gustafsson Dipartimento di Fisica e Geologia and INFN Sezione di Perugia1-06123 PerugiaItaly Laboratori Nazionali di Frascati dell'INFN 1-00044 FrascatiItaly Dipartimento di Ingegneria dell'Informazione Brescia1-25133 BresciaItaly INFN Sezione di Pavia1-27100 PaviaItaly DPhN IRFUCEAUniversitéParis-Saclay1-91191 Gif-sur-Yvette CedexFrance

The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].

关键词： BESⅢ precise

Plasmonics of regular shape particles,a simple group theory approach

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Nano Research 2020年第6期13卷 1597-1603页

作者： Sarra Mitiche Sylvie Marguet Fabrice Charra Ludovic Douillard Université paris-saclay CEACNRSSPECF-91191Gif sur YvetteFrance Université paris-saclay CEACNRSNIMBEF-91191Gif sur YvetteFrance

A simple hand calculation method based on group theory is proposed to predict the near field maps of finite metallic nanoparticles(MNP)of canonical geometries:prism,cube,hexagon,disk,sphere,etc.corresponding to low order localized surface plasmon resonance excitations.In this article,we report the principles of the group theory approach and demonstrate,through several examples,the general character of the group theory method which can be applied to describe the plasmonic response of particles of finite or infinite symmetry point groups.Experimental validation is achieved by collection of high-resolution subwavelength near-field maps by photoemission electron microscopy(PEEM)on a representative set of Au colloidal particles exhibiting either finite(hexagon)or infinite(disk,sphere)symmetry point groups.

关键词： surface plasmon resonance group theory hexagon disk sphere photoemission electron microscopy(PEEM)

Electrochemical reactivity of In-Pb solid solution as a negative electrode for rechargeable Mg-ion batteries

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Journal of Energy Chemistry 2021年第4期30卷 124-128页

作者： Lucie Blondeau Suzy Surble Eddy Foy Hicham Khodja Magali Gauthier Universitéparis-saclay CEACNRSNIMBELEEL91191Gif-sur-YvetteFrance Universitéparis-saclay CEACNRSNIMBELAPA-IRAMAT91191Gif-sur-YvetteFrance

A composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg.A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction analyses.The potential profile of the solid solution indicates the formation of Mg_(2)Pb and Mg In.However,the diffraction study suggests a peculiar electrochemically-driven amorphization of Mg In during the magnesiation,in strong contrast to Mg In crystallization in In-based and In Bi-based electrodes reported in the literature.Combining In and Pb favors the amorphization of Mg In and a high first magnesiation capacity of about 550 m Ah g^(-1),but is thereafter detrimental to the material’s reversibility.These results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials.

关键词： Magnesium battery Negative electrode Alloy Amorphization

Analytical modelling of the expansion of a solid obstacle interacting with a radiative shock

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High Power Laser Science and Engineering 2018年第2期6卷 123-132页

作者： Th.Michel E.Falize B.Albertazzi G.Rigon Y.Sakawa T.Sano H.Shimogawara R.Kumar T.Morita C.Michaut A.Casner R Barroso P.Mabey Y.Kuramitsu S.Laffite L.Van Box Som G.Gregori R.Kodama N.Ozaki P.Tzeferacos D.Lamb M.Koenig luli-cnrs ecole polytechniquecea:universite paris-saclayupmc univ paris 06:sorbonne universites-f-91128 palaiseau cedexFrance cea damdifF-91297 ArpajonFrance cea saclay dsm/irfu/service d'astrophysiqueF-91191 Gif-sur-YvetteFrance institute of laser engineering osaka universitySuitaOsaka 565-0871Japan faculty of engineering sciences kyushu university6-1 Kasuga-KoenKasugaFukuoka 816-8580Japan luth observatoire de parispsl research universitycnrsuniversite paris diderotSorbonne Paris Cite92190 MeudonFrance universite de bordeaux-cnrs-cea celia UMR 5107F-33405 TalenceFrance gepi observatoire de parispsl research universitycnrsuniversite paris diderotSorbonne Paris Cite75014 ParisFrance graduate school of engineering osaka universitySuitaOsaka 565-0871Japan lerma observatoire de parispsl research universitycnrssorbonne universitesUPMC Univ.Paris 06F-75005 ParisFrance clarendon laboratory university of oxfordParks RoadOxford OX1 3PUUK flash center for computational science university of chicagoIL 60637USA

In this paper, we present a model characterizing the interaction of a radiative shock(RS) with a solid material, as described in a recent paper(Koenig et al., Phys. Plasmas, 24, 082707(2017)), the new model is then related to recent experiments performed on the GEKKO XII laser facility. The RS generated in a xenon gas cell propagates towards a solid obstacle that is ablated by radiation coming from the shock front and the radiative precursor, mimicking processes occurring in astrophysical phenomena. The model presented here calculates the dynamics of the obstacle expansion,which depends on several parameters, notably the geometry and the temperature of the shock. All parameters required for the model have been obtained from experiments. Good agreement between experimental data and the model is found when spherical geometry is taken into account. As a consequence, this model is a useful and easy tool to infer parameters from experimental data(such as the shock temperature), and also to design future experiments.

关键词： high energy density physics laser–plasmas interaction modelling plasmas astrophysics plasma physics radiative hydrodynamics radiative shock

Reflecting petawatt lasers off relativistic plasma mirrors:a realistic path to the Schwinger limit

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High Power Laser Science and Engineering 2021年第1期9卷 56-68页

作者： Fabien Quéré Henri Vincenti LIDYL CEA-CNRSUniversitéParis-Saclay91191 Gif-sur-YvetteFrance

The quantum vacuum plays a central role in physics. Quantum electrodynamics(QED) predicts that the properties of the fermionic quantum vacuum can be probed by extremely large electromagnetic fields. The typical field amplitudes required correspond to the onset of the ‘optical breakdown’ of this vacuum, expected at light intensities>4.7×10^(29) W/cm^(2). Approaching this ‘Schwinger limit’ would enable testing of major but still unverified predictions of power lasers. To close this considerable gap, a promising paradigm consists of reflecting these laser beams off a mirror in relativistic motion, to induce a Doppler effect that compresses the light pulse in time down to the attosecond range and converts it to shorter wavelengths, which can then be focused much more tightly than the initial laser light. However, this faces a major experimental hurdle: how to generate such relativistic mirrors? In this article, we explain how this challenge could nowadays be tackled by using so-called ‘relativistic plasma mirrors’. We argue that approaching the Schwinger limit in the coming years by applying this scheme to the latest generation of petawatt-class lasers is a challenging but realistic objective.

关键词： ultraintense laser-matter interaction strong-field quantum electrodynamics plasma mirrors attosecond light pulses

Enhanced ion acceleration using the high-energy petawatt PETAL laser

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Matter and Radiation at Extremes 2021年第5期6卷 62-79页

作者： D.Raffestin L.Lecherbourg I.Lantúejoul B.Vauzour P.E.Masson-Laborde X.Davoine N.Blanchot J.L.Dubois X.Vaisseau E.d’Humières L.Gremillet A.Duval Ch.Reverdin B.Rosse G.Boutoux J.E.Ducret Ch.Rousseaux V.Tikhonchuk D.Batani cea DAMCESTAF-33116 Le BarpFrance Centre Laser Intenses et Applications Universit´e de Bordeaux-CNRS-CEAUMR 510733405 TalenceFrance cea DAMDIFF-91297 ArpajonFrance Universit´e paris-saclay CEALMCE91680 Bruy`eres-le-ChˆatelFrance cea DRFIRFUGANILF-14000 CaenFrance ELI-Beamlines Research Centre 25241 DolníBrezanyCzech Republic

The high-energy petawatt PETAL laser system was commissioned at cea’s Laser M´egajoule facility during the 2017–2018 period.This paper reports in detail on the first experimental results obtained at PETAL on energetic particle and photon generation from solid foil targets,with special emphasis on proton acceleration.Despite a moderately relativistic(<1019 W/cm^(2))laser intensity,proton energies as high as 51 MeV have been measured significantly above those expected from preliminary numerical simulations using idealized interaction conditions.Multidimensional hydrodynamic and kinetic simulations,taking into account the actual laser parameters,show the importance of the energetic electron production in the extended low-density preplasma created by the laser pedestal.This hot-electron generation occurs through two main pathways:(i)stimulated backscattering of the incoming laser light,triggering stochastic electron heating in the resulting counterpropagating laser beams;(ii)laser filamentation,leading to local intensifications of the laser field and plasma channeling,both of which tend to boost the electron acceleration.Moreover,owing to the large(∼100μm)waist and picosecond duration of the PETAL beam,the hot electrons can sustain a high electrostatic field at the target rear side for an extended period,thus enabling efficient target normal sheath acceleration of the rear-side protons.The particle distributions predicted by our numerical simulations are consistent with the measurements.

关键词： acceleration high energy

How accurately can we predict synthesis cross sections of superheavy elements？

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Nuclear Science and Techniques 2018年第12期29卷 15-20页

作者： David Boilley Bartholome Cauchois Hongliang Lu Anthony Marchix Yasuhisa Abe Caiwan Shen GANIL CEA/DRF-CNRS/IN2P3 Caen France Normandie Universite Unicaen Caen France irfu-cea Universite Paris-Saclay Gif-sur-Yvette France RCNP Osaka University Ibaraki-shi Japan School of Science Huzhou University Huzhou 313000China

Synthesis of superheavy elements beyond oganesson is facing new challenges as new target–projectile combinations are necessary. Guidance from models is thus expected for future experiments. However, hindered fusion models are not well established and predictions in the fission barriers span few MeVs. Consequently, predictions are not reliable. Strategies to constrain both fusion hindrance and fission barriers are necessary to improve the predictive power of the models. But, there is no hope to get an accuracy better than one order of magnitude in fusion–evaporation reactions leading to superheavy elements synthesis.

关键词：超重元素合成预言十字节地能模型精确性数量级

Preface to special topic on information and intelligent metasurfaces

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National Science Review 2023年第8期10卷 7-8页

作者： Tie Jun Cui Marco Di Renzo Southeast University Université paris-saclay

In the past decades, information science and technology has developed rapidly, but has also encountered some bottlenecks.Its further development requires some original driving force of underlying physics(such as quant...

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