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Prospect of ultrahigh-resolution fast neutron absorption spectroscopy based on a laser plasma electron accelerator

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High Power Laser Science and engineering 2024年第1期12卷 108-115页

作者： Wen-Zhao Wang Jie Feng Xiao-Peng Zhang Yao-Jun Li Wei-Jun Zhou Wen-Chao Yan Guo-Qiang Zhang Chang-Bo Fu Li-Ming Chen Key Laboratory of Laser Plasma(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghaiChina Institute of High Energy physics Chinese Academy of SciencesBeijingChina Shanghai Advanced Research Institute Chinese Academy of SciencesShanghaiChina Key Laboratory of nuclear physics and Ion-beam Application(MoE) Institute of Modern PhysicsFudan UniversityShanghaiChina

Fast neutron absorption spectroscopy is widely used in the study of nuclear structure and element analysis. However,due to the traditional neutron source pulse duration being of the order of nanoseconds, it is difficult to obtain a high-resolution absorption spectrum. Thus, we present a method of ultrahigh energy-resolution absorption spectroscopy via a high repetition rate, picosecond duration pulsed neutron source driven by a terawatt laser. The technology of single neutron count is used, which results in easily distinguishing the width of approximately 20 keV at 2 MeV and an asymmetric shape of the neutron absorption peak. The absorption spectroscopy based on a laser neutron source has one order of magnitude higher energy-resolution power than the state-of-the-art traditional neutron sources, which could be of benefit for precisely measuring nuclear structure data.

关键词： fast neutron absorption spectroscopy laser plasma accelerator photo-nuclear neutrons single neutron count

Evolution of nonmetallic inclusions in 80-t 9CrMoCoB large-scale ingots during electroslag remelting process

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1525-1539页

作者： Shengchao Duan Min Joo Lee Yao Su Wangzhong Mu Dong Soo Kim Joo Hyun Park School of Mechanical and Materials engineering North China University of TechnologyBeijing 100144China department of Materials Science and Chemical engineering Hanyang UniversityAnsan 15588Rep.of Korea department of Materials Science and engineering KTH Royal Institute of TechnologyBrinellvägen 23Stockholm 10044Sweden department of engineering Science and Mathematics Division of Materials ScienceLuleåUniversity of Technology97187 LuleåSweden Casting&Forging Business Unit Nuclear Business GroupDoosan EnerbilityChangwon 51711Rep.of Korea

In combination with theoretical calculations,experiments were conducted to investigate the evolution behavior of nonmetallic inclusions(NMIs)during the manufacture of large-scale heat-resistant steel ingots using 9CrMoCoB heat-resistant steel and CaF_(2)–CaO–Al_(2)O_(3)–SiO_(2)–B_(2)O_(3)electroslag remelting(ESR)-type slag in an 80-t industrial ESR *** main types of NMI in the consumable electrode comprised pure alumina,a multiphase oxide consisting of an Al_(2)O_(3)core and liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO shell,and M_(23)C_(6)carbides with an MnS *** Al_(2)O_(3)and MnS inclusions had higher precipitation temperatures than the M_(23)C_(6)-type carbide under equilibrium and nonequilibrium solidification ***,inclusions can act as nucleation sites for carbide layer *** ESR process completely removed the liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO oxide and MnS inclusion with a carbide shell,and only the Al_(2)O_(3)inclusions and Al_(2)O_(3)core with a carbide shell occupied the remelted *** M_(23)C_(6)-type carbides in steel were determined as Cr_(23)C_(6)based on the analysis of transmission electron microscopy *** substitution of Cr with W,Fe,or/and Mo in the Cr_(23)C_(6)lattice caused slight changes in the lattice parameter of the Cr_(23)C_(6)***,Cr_(21.34)Fe_(1.66)C_(6),(Cr_(19)W_(4)C_(6),Cr_(18.4)Mo_(4.6)C_(6),and Cr_(16)Fe_(5)Mo_(2)C_(6)can match the fraction pattern of Cr_(23)C_(6)*** Al_(2)O_(3)inclusions in the remelted ingot formed due to the reduction of CaO,SiO_(2),and MnO components in the liquid *** increased Al content in liquid steel or the higher supersaturation degree of Al_(2)O_(3)precipitation in the remelted ingot than that in the electrode can be attributed to the evaporation of CaF_(2)and the increase in CaO content in the ESR-type slag.

关键词： nonmetallic inclusion heat-resistant steel electroslag remelting M_(23)C_(6) carbide MnS inclusion supersaturation degree

Dynamical control of nanoscale light-matter interactions in low-dimensional quantum materials

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Light(Science & Applications) 2024年第2期13卷 236-253页

作者： Yeonjeong Koo Taeyoung Moon Mingu Kang Huitae Joo Changjoo Lee Hyeongwoo Lee Vasily Kravtsov Kyoung-Duck Park department of physics Pohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea School of physics and engineering ITMO UniversitySaint Petersburg197101Russia

Tip-enhanced nano-spectroscopy and-imaging have significantly advanced our understanding of low-dimensional quantum materials and their interactions with light,providing a rich insight into the underlying physics at their natural length ***,various functionalities of the plasmonic tip expand the capabilities of the nanoscopy,enabling dynamic manipulation of light-matter interactions at the *** this review,we focus on a new paradigm of the nanoscopy,shifting from the conventional role of imaging and spectroscopy to the dynamical control approach of the tip-induced light-matter *** present three different approaches of tip-induced control of light-matter interactions,such as cavity-gap control,pressure control,and near-field polarization ***,we discuss the nanoscale modifications of radiative emissions for various emitters from weak to strong coupling regime,achieved by the precise engineering of the ***,we introduce recent works on light-matter interactions controlled by tip-pressure and near-field polarization,especially tunability of the bandgap,crystal structure,photoluminescence quantum yield,exciton density,and energy transfer in a wide range of quantum *** envision that this comprehensive review not only contributes to a deeper understanding of the physics of nanoscale light-matter interactions but also offers a valuable resource to nanophotonics,plasmonics,and materials science for future technological advancements.

关键词： quantum precise shifting

Investigation of an electrode-driven hydrogen plasma method for in situ cleaning of tin-based contamination

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Plasma Science and Technology 2024年第8期26卷 73-83页

作者：彭怡超叶宗标王思蜀蒲国刘显洋苑聪聪廖加术韦建军余新刚芶富均 Key Laboratory of Radiation physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064People’s Republic of China Institute of Atomic and Molecular physics Sichuan UniversityChengdu 610064People’s Republic of China Institute of High Performance Scientific Computation Xihua UniversityChengdu 610039People’s Republic of China School of engineering Science University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power *** tin-based contamination consisting of micro-and macroparticles was deposited on silicon via physical vapor deposition(PVD).The electrodedriven hydrogen plasma at different power levels was systematically diagnosed using a Langmuir probe and a retarding field ion energy analyzer(RFEA).Moreover,the magnitude of the self-biasing voltage was measured at different power levels,and the peak ion energy was corrected for the difference between the RFEA measurements and the self-biasing voltage(E_(RFEA)-eV_(self)).XPS analysis of O 1s and Sn 3d peaks demonstrated the chemical reduction process after 1 W *** of surface and cross-section morphology revealed that holes emerged on the upper part of the macroparticles while its bottom remained *** and folds appeared on the upper part of the microparticles,confirming the top-down cleaning mode with hydrogen *** study provides an in situ electrode-driven hydrogen plasma etching process for tin-based contamination and will provide meaningful guidance for understanding the chemical mechanism of reduction and etching.

关键词： tin-based contamination hydrogen plasma in situ cleaning ion energy

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology department of Materials Science and engineering City University of Hong Kong Key Laboratory of Partial Acceleration physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences department of Materials Science &engineering Southern University of Science and Technology department of physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

Spatial and temporal evolution of electromagnetic pulses from solid target irradiated with multi-hundred-terawatt laser pulse inside target chamber

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Plasma Science and Technology 2024年第2期26卷 62-69页

作者：何强友邓志刚张智猛夏亚东张博孟令彪贺书凯黄华杨雷刘红杰范伟林晨周维民李廷帅颜学庆 State Key Laboratory of nuclear physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871People's Republic of China Science and Technology on Plasma physics Laboratory Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900People's Republic of China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731People's Republic of China Beijing Laser Acceleration Innovation Center Beijing 101400People's Republic of China

Giant electromagnetic pulses(EMPs) induced by high-power laser irradiating solid targets interfere with various experimental diagnoses and even damage equipment,so unveiling the evolution of EMPs inside the laser chamber is crucial for designing effective EMP *** this work,the transmission characteristics of EMPs as a function of distances from the target chamber center(TCC) are studied using B-dot *** mean EMP amplitude generated by picosecond laser-target interaction reaches 561 kV m^(-1),357 kV m^(-1),395 kV m^(-1),and 341 kV m^(-1)at 0.32 m,0.53 m,0.76 m,and 1 m from TCC,which decreases dramatically from 0.32 m to 0.53 ***,it shows a fluctuation from 0.53 m to 1 *** temporal features of EMPs indicate that time-domain EMP signals near the target chamber wall have a wider full width at half maximum compared to that close to TCC,mainly due to the echo oscillation of electromagnetic waves inside the target chamber based on simulation and *** conclusions of this study will provide a new approach to mitigate strong electromagnetic pulses by decreasing the echo oscillation of electromagnetic waves inside the target chamber during laser coupling with targets.

关键词： target electromagnetic pulses spatial distribution

Speed limit effect during lane change in a two-lane lattice model under V2X environment

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Chinese physics B 2024年第3期33卷 718-722页

作者：金灿彭光含聂方彦 College of Physical Science and Technology Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of nuclear physics and Technology Guangxi Normal UniversityGuilin 541004China Information and Modern Education Technology Center Hunan University of Arts and ScienceChangde 415000China Computer and Information engineering College Guizhou University of CommerceGuiyang 550014China

Speed limit measures are ubiquitous due to the complexity of the road environment,which can be supplied with the help of vehicle to everything(V2X)communication ***,the influence of speed limit on traffic system will be investigated to construct a two-lane lattice model accounting for the speed limit effect during the lane change process under V2X ***,the stability condition and the mKdV equation are closely associated with the speed limit effect through theory ***,the evolution of density and hysteresis loop is simulated to demonstrate the positive role of the speed limit effect on traffic stability in the cases of strong reaction intensity and high limited speed.

关键词： traffic flow lattice model speed limit

Correlation function and the inverse problem in the BD interaction

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Chinese physics C 2024年第5期48卷 117-123页

作者：李海鹏义景宇肖褚文姚德良梁伟红 Eulogio Oset department of physics Guangxi Normal UniversityGuilin 541004China School of physics and Electronics Hunan UniversityChangsha 410082China Guangxi Key Laboratory of nuclear physics and Technology Guangxi Normal UniversityGuilin 541004China School of physics Central South UniversityChangsha 410083China Departamento de Física Teórica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de PaternaAptdo.2208546071 ValenciaSpain

We study the correlation functions of the B0D+,B+D0 system,which develops a bound state of approximately 40MeV,using inputs consistent with the Tcc(3875)***,we address the inverse problem starting from these correlation functions to determine the scattering observables related to the system,including the existence of the bound state and its molecular *** important output of the approach is the uncertainty with which these observables can be obtained,considering errors in the B0D+,B+D0 correlation functions typical of current values in correlation *** find that it is possible to obtain scattering lengths and effective ranges with relatively high precision and the existence of a bound *** the pole position is obtained with errors of the order of 50%of the binding energy,the molecular probability of the state is obtained with a very small error of the order of 6%.All these findings serve as motivation to perform such measurements in future runs of high energy hadron collisions.

关键词： meson-meson interaction correlation function BD system scattering observables

Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(physics,Mechanics & Astronomy) 2024年

作者： Ligong Bian Shuailiang Ge Changhong Li Jing Shu Junchao Zong department of physics and Chongqing Key Laboratory for Strongly Coupled physics Chongqing University Center for High Energy physics Peking University School of physics and State Key Laboratory of nuclear physics and Technology Peking University department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan Province School of Physics and AstronomyYunnan University Beijing Laser Acceleration Innovation Center department of physics Nanjing University CAS Key Laboratory of Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences

We explore the possibility that domain wall networks generate the stochastic gravitational wave background （SGWB） observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing *** find that a broad range of parameters,specifically wall tension aroundσDW～（29-414 TeV）3and wall-decay temperature within Td～20-257 MeV,can explain this phenomenon at a 68%credible ***,the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark *** establish a direct analytical relationship,?GW（fp,T0）h2～?radh2(?ν?Neff)2,to illustrate this coincidence,underlining its importance in the underlying physics and potential applicability to a wider range of models and ***,if the common power-law process is not attributed to domain wall networks,our findings impose tight limits on the wall tension and decay temperature.

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