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Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 2. MeV on the Back-n at CSNS

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nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： Jie-Ming Xue Song Feng Yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu Yi-Wei Yang Zi-Jie Han Da-Jun Zhao Hao-Qiang Wang Bao-Qian Li Ji-Rong Zhao Lei-Xun Tang Wen Luo Bo Zheng School of nuclear Science and Technology University of South ChinaHengyang 421001China Institute of High Energy physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science center Dongguan 523803China Institute of nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-2. MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron *** energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission *** on-beam background was determined using Co,In,Ag,and Cd *** excitation function of ^(nat)Pb(n,tot)reaction below 2. MeV was calculated using the TALYS-1.96 nuclear-reaction modeling *** present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2.and BROND-3.1),and the {2. calculation *** agreement was found between the new results and those of previous experiments and with the {2. curves in the corresponding *** measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy *** provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline

Gravitational wave footprints from Higgs-portal scalegenesis with multiple dark chiral scalars

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Chinese physics C 2024年第4期 213-225页

作者：张贺旭 Shinya Matsuzaki Hiroyuki Ishida center for theoretical {2. and College of {2. Jilin University center for Liberal Arts and Sciences Toyama Prefectural University

We discuss the gravitational wave(GW) spectra predicted from the electroweak scalegenesis of the Higgs portal type with a large number of dark chiral flavors, which many flavor QCD would underlie and give the dynamical explanation of the negative Higgs portal coupling required to trigger the electroweak symmetry *** employ the linear-sigma model as the low-energy description of dark many flavor QCD and show that the model undergoes ultra-supercooling due to the produced strong first-order thermal phase transition along the(approximately realized) flat direction based on the Gildener-Weinberg mechanism. Passing through evaluation of the bubble nucleation/percolation, we address the reheating and relaxation processes, which are generically non-thermal and nonadiabatic. Parametrizing the reheating epoch in terms of the e-folding number, we propose proper formulae for the redshift effects on the GW frequencies and signal spectra. It then turns out that the ultra-supercooling predicted from the Higgs-portal scalegenesis generically yields none of GW signals with the frequencies as low as nano Hz,unless the released latent heat is transported into another sector other than reheating the universe. Instead, models of this class prefer to give the higher frequency signals and still keeps the future prospected detection sensitivity, like at LISA, BBO, and DECIGO, etc. We also find that with large flavors in the dark sector, the GW signals are made further smaller and the peak frequencies higher. Characteristic phenomenological consequences related to the multiple chiral scalars include the prediction of dark pions with the mass much less than Te V scale, which is also briefly addressed.

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A versatile model with three-dimensional triangular lattice for unconventional transport and various topological effects

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National Science Review 2024年第1期11卷 204-214页

作者： Jing-Yang You Gang Su Yuan Ping Feng Department of physics National University of Singapore Kavli Institute for theoretical Sciences and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Centre for Advanced 2. Materials National University of Singapore

The finite Berry curvature in topological materials can induce many subtle phenomena, such as the anomalous Hall effect(AHE), spin Hall effect(SHE), anomalous Nernst effect(ANE), non-linear Hall effect(NLHE) and bulk photovoltaic effects. To explore these novel physics as well as their connection and coupling, a precise and effective model should be developed. Here, we propose such a versatile model—a 3D triangular lattice with alternating hopping parameters, which can yield various topological phases,including kagome bands, triply degenerate fermions, double Weyl semimetals and so on. We reveal that this special lattice can present unconventional transport due to its unique topological surface states and the aforementioned topological phenomena, such as AHE, ANE, NLHE and the topological photocurrent effect. In addition, we also provide a number of material candidates that have been synthesized experimentally with this lattice, and discuss two materials, including a non-magnetic triangular system for SHE, NLHE and the shift current, and a ferromagnetic triangular lattice for AHE and ANE. Our work provides an excellent platform, including both the model and materials, for the study of Berry-curvature-related physics.

关键词： three-dimensional triangular lattice different topological phases various topological effects Berry curvature

Search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using CMS open data

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Chinese physics C 2024年第4期48卷 6-13页

作者： Y.Mahmoud H.Abdallah M.T.Hussein S.Elgammal Centre for theoretical physics The British University in EgyptEgypt physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the CMS experiment during run-I of the LHC in 2.12.with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−*** data were gathered from the CMS open *** matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMS open *** evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CMS open data search for new physics dark fermion

Cholesterol-induced deformation of the gramicidin A channel inhibiting potassium ion binding and transport

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Chinese physics B 2024年第5期33卷 696-702页

作者：肖盼曹宇朱瑾梁清 center for Statistical and theoretical Condensed Matter {2. & Department of {2. Zhejiang Normal UniversityJinhua 321004China Zhejiang Institute of Photoelectronics & Zhejiang Institute for Advanced Light Source Zhejiang Normal UniversityJinhua 321004China

Gramicidin A(gA)is a kind of antibiotic peptide produced by bacillus brevis and it can dimerize across lipid bilayers to form a monovalent cation *** this work,we investigate the impact of cholesterol in the lipid bilayer on the binding of potassium ions with the gA channel and the transport of the ions across the *** results indicate that cholesterol can significantly influence the conformational stability of the gA channel and cause the channel deformation which inhibits the potassium ion binding with the channel and transport across the *** work provides some molecular insights into understanding of influence of lipids on the activity of gA channel in both model membranes and plasma membranes of intact cells.

关键词： gramicidin A lipid bilayer molecular dynamics interaction

Possibilities for the synthesis of superheavy element Z=12. in fusion reactions

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nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao Zhang Yu-Hai Zhang Ying Zou Xiu-Xiu Yang Gen Zhang Feng-Shou Zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=12. was systematically studied through combinations of stable projectiles with Z=2.-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(2.4)Es(^(46)Ti,3n)^(2.7)12. and^(2.2.Es(^(46)Ti,3n)^(2.5)12. were found to be experimentally feasible for synthesizing superheavy element Z=12.,with maximal evaporation residue cross sections of 6.619 and 4.12. fb at 2.9.9 and 2.3.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

The preface: Interplay of topological and magnetic orders in the Mn-Bi-Te family

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National Science Review 2024年第2期11卷 6-7页

作者： Fu-Chun Zhang Hai-Zhou Lu X.C.Xie Kavli Institute for theoretical Sciences University of Chinese Academy of Sciences Department of physics Southern University of Science and Technology (SUSTech) International center for Quantum Materials School of Physics Peking University

The discovery and synthesis of MnBi2.e4in 2.13 initially garnered little attention [1]. Yet, the revelation of its topological properties in 2.19 [2.6] sparked a surge of research into the MnBiTe family. These extensive studies are primarily driven by two objectives:the realization of a high-temperature quantum anomalous Hall effect （QAHE） and the exploration of exotic phases born from the interplay of topological and magnetic orders,

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SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko L.V.Kalinovskaya A.A.Kampf R.R.Sadykov V.L.Yermolchyk Bogoliubov Laboratory of theoretical physics JINRDubna141980 Russia Dzhelepov Laboratory of nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 2.0 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Gravitational form factors of the proton from near-threshold vector meson photoproduction

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Chinese physics C 2024年第5期48卷 226-234页

作者：王晓云曾凡聪张纪元 Department of physics Lanzhou University of TechnologyLanzhou 730050China Lanzhou center for theoretical {2. Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Institute of High Energy physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

We systematically analyze the quark and gluon gravitational form factors(GFFs)of the proton by connecting the energy-momentum tensor and near-threshold vector meson photoproduction(NTVMP).Specifically,the quark contributions of GFFs are determined by applying global fitting to the cross section of the lightest vector mesonρ0 *** with the gluon GFFs obtained from heavy quarkonium J/ψphotoproduction data,the complete GFFs are obtained and compared with the experimental results and lattice quantum chromodynamics *** addition,we use the resonance via Padé(RVP)method based on the Schlessinger point method to obtain a model-independent quark D-term distribution through direct analytical continuation of deeply virtual Compton scattering experimental *** errors are considered,the results obtained with RVP are essentially consistent with those obtained by ***,the comprehensive information on GFFs helps to uncover the mass distribution and mechanical properties inside the *** study is not only an important basis for delving into the enigmatic properties of the proton,but also has significance for theoretically guiding future JLab and EIC experimental measurements.

关键词： gravitational form factors properties of the proton vector mesonphotoproduction Schlessinger point method