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质子磁荷半径:新疑难?

Science Bulletin 2024年第4期69卷 419-421页

作者：林勇辉 Hans-Werner Hammer Ulf-G.Meiûner Helmholtz institut für Strahlen-und kernphysik and Bethe Center for Theoretical Physics Universität BonnBonn D-53115Germany Technische Universität Darmstadt Department of PhysicsInstitut für KernphysikDarmstadt 64289Germany ExtreMe Matter institute EMMI and Helmholtz forschungsakademie Hessen für fAIr GSI Helmholtzzentrum für Schwerionenforschung GmbHDarmstadt 64291Germany institute for Advanced Simulation and institut für kernphysik Forschungszentrum JülichJülich D-52425Germany Tbilisi State University Tbilisi 0186Georgia

The electric radius,rE,and the magnetic radius,rM,of the proton are fundamental quantities of low-energy QCD,as they are a measure of the probe-dependent size of the proton.

关键词： radius quantities fundamental

ABNOrMAL INCrEASE Of HNO_3 CONCENTrATION IN THE EI CHICHON VOLCANIC CLOUDS

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Chinese Science Bulletin 1988年第7期33卷 591-595页

作者：邱时彦 f.ArNOLD institute of Space Physics Academia Sinica Belling Max-Planck-institut für kernphysik

The March 28 and April 4, 1982 eruptions of the E1 Chichon volcano produced the densest dust cloud of this century in the stratosphere which provided an unprecedented opportunity to study aerosol and its weather and c... 详细信息

关键词： aerosol opportunity climatic unprecedented weather cloud Aerosol minor latitude constituent

Ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuALitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Max-Planck-institut für kernphysik Saupfercheckweg 169117 HeidelbergGermany GSI Helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology Guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in Lanzhou.The new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 keV.When compared to the analogue states in its mirror nucleus ^(22)f,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)f mirror pair are determined to be−625(51)keV and−330(51)keV.The excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field theory.The mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSrG calculations chiral interactions

Extracting the low-energy constant L_(0)^(r)at three flavors from pion-kaon scattering

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Communications in Theoretical Physics 2022年第6期74卷 61-65页

作者： Chaitra Kalmahalli Guruswamy Ulf-G Meißner Chien-Yeah Seng Helmholtz-institut für Strahlen-und kernphysik and Bethe Center for Theoretical Physics Universität BonnD-53115 BonnGermany institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany Tbilisi State University 0186 TbilisiGeorgia

based on our analysis of the contributions from the connected and disconnected contraction diagrams to the pion-kaon scattering amplitude,we provide the first determination of the only free low-energy constant at O(p^(4)),known as L_(0)^(r),in SU(4|1)Partially-Quenched Chiral Perturbation theory using the data from the Extended Twisted Mass collaboration,L_(0)^(r)(μ=M_(ρ))=0.77(20)(25)(7)(7)(2)·10^(-3).The theory uncertainties originate from the unphysical scattering length,the physical low-energy constants,the higher-order chiral corrections,the(lattice)meson masses and the pion decay constant,respectively.

关键词： lattice QCD partially quenched chiral perturbation theory pion-kaon scattering

Evolution of N=20,28,50 shell closures in the 20≤Z≤30 region in deformed relativistic Hartree-Bogoliubov theory in continuum

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Chinese Physics C 2024年第1期48卷 144-153页

作者：郑茹尤孙向向申国防耿立升 School of Physics Beihang UniversityBeijing102206China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China institut für kernphysik Institute for Advanced Simulation and Jülich Center for Hadron PhysicsForschungszentrum JülichD-52425 JülichGermany CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Peng Huanwu Collaborative Center for research and Education Beihang UniversityBeijing 100191China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 102206China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

Magicity,or shell closure,plays an important role in our understanding of complex nuclear phenomena.In this work,we employ one of the state-of-the-art density functional theories,the deformed relativistic Hartree-Bogoliubov theory in continuum(DrHBc)with the density functional PC-PK1,to investigate the evolution of the N=20,28,50 shell closures in the 20≤Z≤30 region.We show how these three conventional shell closures evolve from the proton drip line to the neutron drip line by studying the charge radii,two-neutron separation energies,two-neutron gaps,quadrupole deformations,and single-particle levels.In particular,we find that in the 21≤Z≤27 region,the N=50 shell closure disappears or becomes quenched,mainly due to the deformation effects.Similarly,both experimental data and theoretical predictions indicate that the N=28 shell closure disappears in the Mn isotopic chain,mainly due to the deformation effects.The DrHBc theory predicts the existence of the N=20 shell closure in the Ca,Sc,and Ti isotopic chains,but the existing data for the Ti isotopes suggest the contrary,and therefore further research is needed.

关键词： shell evolution covariant density functional theories magic numbers

Measurement of the pion form factor for M_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOE detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan E.Müller institut für kernphysik Johannes Gutenberg-Universitt

The KLOE experiment at the φ-factory DAФPNE has measured the pion form factor in the range between 0.1 〈 Mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the Mππ^2 region covered by KLOE ISr measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard Model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

Production of the X(4014)as the Spin-2 Partner of X(3872)in e^(+)e^(-)Collisions

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Chinese Physics Letters 2024年第3期41卷 30-36页

作者： Pan-Pan Shi Vadim Baru feng-Kun Guo Christoph Hanhart Alexey Nefediev CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Departamento de f′ısica Te′orica and IfIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigaci′on de PaternaAptdo.2208546071 ValenciaSpain institut fur Theoretische Physik II Ruhr-Universitat BochumD-44780 BochumGermany Peng Huanwu Collaborative Center for research and Education Beihang UniversityBeijing 100191China institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Jozef Stefan institute Jamova 391000LjubljanaSlovenia CefEMA Center of Physics and Engineering of Advanced MaterialsInstituto Superior T′ecnicoAvenida Rovisco Pais 11049-001 LisboaPortugal

In 2021,the Belle collaboration reported the first observation of a new structure in theψ(2S)γfinal state produced in the two-photon fusion process.In the hadronic molecule picture,this new structure can be associatedwith the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872)with the quantum numbers J^(PC)=2^(++)conventionally named X_(2).

关键词： process X(3872) Collisions

Heavy quark spin symmetry and heavy flavor hadronic molecules

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Chinese Physics C 2010年第9期34卷 1294-1297页

作者：郭奉坤 institut für kernphysik and Jülich Center for Hadron Physics

We argue that the heavy quark spin symmetry can lead to important consequences for heavy flavor hadronic molecules.It can be used to predict new heavy flavor hadronic molecules and hence provides a method to identify the nature of some newly observed exotic hadrons.for example,if the Y（4660） were an S-wave ψ f 0 （980） shallow bound state,then the mass,width and line shape of its spin partner are predicted.

关键词： heavy quark spin symmetry hadronic molecules exotic hadrons

Accelerating ions with high-energy short laser pulses from submicrometer thick targets

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： f.Wagner C.Brabetz O.Deppert M.roth T.Stohlker An.Tauschwitz A.Tebartz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH Helmholtz institut Jena institut für kernphysik Technische Universitat Darmstadt institute for Theoretical Physics Frankfurt University

Using the example of the PHELIX high-energy short pulse laser we discuss the technical preconditions to investigate ion acceleration with submicrometer thick targets. We show how the temporal contrast of this system was improved to prevent pre-ionization of such targets on the nanosecond timescale. furthermore the influence of typical fluctuations or uncertainties of the on-target intensity on ion acceleration experiments is discussed. We report how these uncertainties were reduced by improving the assessment and control of the on-shot intensity and by optimizing the positioning of the target into the focal plane. finally we report on experimental results showing maximum proton energies in excess of 85 MeV for ion acceleration via the target normal sheath acceleration mechanism using target thicknesses on the order of one micrometer.

关键词： high-power laser technique laser-ion acceleration relativistic laser plasma interaction target normal sheath acceleration temporal contrast