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Chinese physics B 2024年第9期33卷 268-280页

作者： Luyao Zhang Xiyang Xie department of mathematics and physics Hebei Key Laboratory of Physics and Energy TechnologyNorth China Electric Power UniversityBaoding 071003China

We study the dynamics of fundamental and double-pole breathers and solitons for the focusing and defocusing nonlinearSchr¨odinger equation with the sextic operator under non-zero boundary conditions. Our analysis mainly focuses onthe dynamical properties of simple- and double-pole solutions. Firstly, through verification, we find that solutions undernon-zero boundary conditions can be transformed into solutions under zero boundary conditions, whether in simple-pole ordouble-pole cases. For the focusing case, in the investigation of simple-pole solutions, temporal periodic breather and thespatial-temporal periodic breather are obtained by modulating parameters. Additionally, in the case of multi-pole solitons,we analyze parallel-state solitons, bound-state solitons, and intersecting solitons, providing a brief analysis of their *** the double-pole case, we observe that the two solitons undergo two interactions, resulting in a distinctive “triangle”crest. Furthermore, for the defocusing case, we briefly consider two situations of simple-pole solutions, obtaining one andtwo dark solitons.

关键词： double-pole solitons double-pole breathers Riemann–Hilbert problem non-zero boundary conditions nonlinear Schr¨odinger equation with sextic operator

Davidson base as an appropriate base for the shell model in the case of 1p- and 1h- nuclei

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Communications in Theoretical physics 2024年第10期76卷 94-100页

作者： Hadi Sobhani Yan-An Luo Amir Jalili Hassan Hassanabadi School of physics Nankai University department of physics Zhejiang Sci-Tech University Institute of Theoretical physics Faculty of Physics University of Warsaw Institute of Actuarial Science and Data Analytics UCSI University

This study endeavors to develop an improved set of basis functions for nuclear shell-model calculations. The shell model, a well-established approach to understanding nuclear structure,typically employs the harmonic oscillator potential within the mean-field approximation. Given the extensive validation and consistency of harmonic oscillator results with experimental data,we propose a modification by incorporating a centrifugal term that converges toward the Davidson potential. This potential has been extensively studied, and we aim to extract relevant experimental data for the simplest cases in the shell model, namely one-particle and one-hole nuclei. A comprehensive comparison between the Davidson-based results and the harmonic oscillator calculations is presented to demonstrate the effectiveness of the new basis functions.

关键词： beta decay gamma transition nuclear structure shell-model calculations

Recent advances in protein conformation sampling by combining machine learning with molecular simulation

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Chinese physics B 2024年第3期33卷 80-87页

作者：唐一鸣杨中元姚逸飞周运谈圆王子超潘瞳熊瑞孙俊力韦广红 department of physics State Key Laboratory of Surface Physicsand Key Laboratory for Computational Physical Sciences (Ministry of Education)Shanghai 200438China

The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational *** of the most cutting-edge and important applications of ML is its integration with molecular simulations to improve the sampling efficiency of the vast conformational space of large *** review focuses on recent studies that utilize ML-based techniques in the exploration of protein conformational *** first highlight the recent development of ML-aided enhanced sampling methods,including heuristic algorithms and neural networks that are designed to refine the selection of reaction coordinates for the construction of bias potential,or facilitate the exploration of the unsampled region of the energy ***,we review the development of autoencoder based methods that combine molecular simulations and deep learning to expand the search for protein ***,we discuss the cutting-edge methodologies for the one-shot generation of protein conformations with precise Boltzmann ***,this review demonstrates the promising potential of machine learning in revolutionizing our insight into the complex conformational ensembles of proteins.

关键词： machine learning molecular simulation protein conformational space enhanced sampling

Revisiting the top-quark pair production at future e^(+)e^(−)colliders

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Chinese physics C 2024年第4期48卷 82-88页

作者：马进王声权孙婷申建明吴兴刚 department of physics Guizhou Minzu UniversityGuiyang 550025China School of physics and Electronics Hunan Provincial Key Laboratory of High-Energy Scale Physics and ApplicationsHunan UniversityChangsha 410082China department of physics Chongqing Key Laboratory for Strongly Coupled PhysicsChongqing UniversityChongqing 401331China

In this study,we reanalyze the top-quark pair production at next-to-next-to-leading order(NNLO)in quantum chromodynamics(QCD)at future e^(+)e^(−)colliders using the Principle of Maximum Conformality(PMC)*** PMC renormalization scales inαs are determined by absorbing the non-conformalβterms by recursively using the Renormalization Group Equation(RGE).Unlike the conventional scale-setting method of fixing the scale at the center-of-mass energyμ_(r)=√s,the determined PMC scale Q_(⋆)is far smaller than the √sand increases with the √s,yielding the correct physical behavior for the top-quark pair production ***,the convergence of the pQCD series for the top-quark pair production is greatly improved owing to the elimination of the renormalon *** a typical collision energy of √s=500 GeV,the PMC scale is Q_(⋆)=107 GeV;the QCD correction factor K for conventional results is K∼1+0.1244+0.0102+0.0012−0.0087−0.0011+0.0184−0.0086+0.0002+0.0061−0.0003,where the first error is caused by varying the scaleμr∈[√s/2,2√s]and the second error is from the top-quark massΔm_(t)=±0.7 *** applying the PMC,the renormalization scale uncertainty is eliminated,and the QCD correction factor K is improved to K∼1+0.1507_(−0.0015)^(+0.0015)−0.0057_(−0.0000)^(+0.0001),where the error is from the top-quark massΔm_(t)=±0.7 *** PMC improved predictions for the top-quark pair production are helpful for detailed studies of the properties of the top-quark at future e^(+)e^(−)colliders.

关键词： top-quark lepton colliders Renormalization Group Equation QCD correction

Tidal effects based on a GUP-induced effective metric

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Communications in Theoretical physics 2024年第9期76卷 63-72页

作者： Soon-Tae Hong Yong-Wan Kim Young-Jai Park Center for Quantum Spacetime and department of physics Sogang UniversitySeoul 04107Republic of Korea department of physics and Research Institute of physics and Chemistry Jeonbuk National UniversityJeonju 54896Republic of Korea department of physics Sogang UniversitySeoul 04107Republic of Korea

In this paper,we study tidal forces in the Schwarzschild black hole,whose metric explicitly includes a generalized uncertainty principle(GUP)*** also investigate interesting features of the geodesic equations and tidal effects that are dependent on the GUP parameterαrelated to a minimum ***,by solving the geodesic deviation equations explicitly with appropriate boundary conditions,we show thatαin the effective metric affects both the radial and angular components of the geodesic equation,particularly near the singularities.

关键词： generalized uncertainty principle geodesic deviation equation effective metric

Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

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Nuclear Science and Techniques 2024年第7期35卷 147-156页

作者： Wei-Jie Dong Xiao-Zhou Yu Si-Yuan Ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-Wei Lin Key Laboratory of Nuclear physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China department of physics and Astronomy University of CaliforniaLos AngelesCA 90095USA department of physics East Carolina UniversityGreenvilleNC 27858USA

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

关键词： Baryon number transport Strangeness conversation Correlation Gluon junction

Doped holographic superconductors in the Gubser–Rocha model

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Communications in Theoretical physics 2024年第4期76卷 80-92页

作者： Ziyi Zhao Wenhe Cai Shuta Ishigaki department of physics Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of High Temperature Superconductors Department of PhysicsShanghai UniversityShanghai 200444China

We construct a doped holographic superconductor in the Gubser–Rocha model,and realize a superconducting dome in the middle of the temperature-doping phase *** is worth noting that unlike in previous research,the profile of our dome shrinks inward near to zero *** the numerical observation for the coupling dependence of the phase diagram,we find that the coupling between the two gauge fields plays a crucial role in the formation of the *** also analytically calculate the DC conductivity of the normal phase of the system in the momentum dissipation and obtain resistivity which is proportional to the *** AC conductivity is calculated numerically.

关键词： AdS-CFT correspondence High-Tc superconductor AC/DC conductivities Gubser-Rocha geometry

The Space-Charge Problem in Ultrafast Diagnostics:An All-Optical Solution for Streak Cameras

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Ultrafast Science 2024年第2期4卷 19-28页

作者： Vassily Kornienko Yupan Bao Joakim Bood Andreas Ehn Elias Kristensson department of physics Lund UniversityLundSweden

The field of ultrafast science is dependent on either ultrashort laser pulse technology or ultrafast passive *** there exists a plethora of sub-picosecond laser pulse solutions,streak cameras are singular in providing sub-picosecond passive imaging ***,their use in fields ranging from medicine to physics is *** cameras attain such temporal resolutions by converting signal photons to ***,the Coulomb repulsion force spreads these electrons spatiotemporally aggravating streak cameras’temporal resolution and dynamic range—an effect that increases in severity in ultrafast applications where electrons are generated nearly *** many electro-optical solutions have been proposed and successfully implemented,this issue remains as a challenge for all sub-picosecond streak camera *** of resorting to electro-optical solutions,in this work,we present an all-optical approach based on the combination of photon tagging and spatial lock-in detection with a technique called periodic shadowing—that is directly applicable to all generations of streak *** have demonstrated that this accessible all-optical solution,consisting of a single externally applied optical component,results in(a)a>3×improvement in dynamic range,(b)a 25%increase in temporal resolution,and(c)a reduction of background noise levels by a factor of 50,which,when combined,allows for a markedly improved accuracy in the measurement of ultrafast signals.

关键词： passive resort resolution

Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij H.C.Swart Vinay Kumar department of physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia department of physics School of SciencesCluster University of JammuCanal RoadJammu180001India department of physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India department of physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Nonlinear corrections for the nuclear gluon distribution in eA processes

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Chinese physics C 2024年第3期48卷 52-64页

作者： G.R.Boroun B.Rezaei F.Abdi department of physics Razi UniversityKermanshah 67149Iran.

An analytical study with respect to the nonlinear corrections for the nuclear gluon distribution function in the next-to-leading order approximation at small x is *** consider the nonlinear corrections to the nuclear gluon distribution functions at low values of x and Q^(2) using the parametrization F_(2)(x,Q^(2))and the nuclear modification factors obtained from the Khanpour-Soleymaninia-Atashbar-Spiesberger-Guzey *** CT18 gluon distribution is used for the baseline proton gluon density at Q^(2)_(0)=*** discuss the behavior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale Q^(2)_(0),as well as the modifications due to the nonlinear *** find that the QCD nonlinear corrections are more significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy *** results of the nonlinear GLR-MQ evolution equation are similar to those obtained with the Rausch-Guzey-Klasen gluon upward and downward evolutions within the *** magnitude of the gluon distribution with the nonlinear corrections increases with a decrease in x and an increase in atomic number A.

关键词： gluon distribution nonlinear corrections light and heavy nuclei low x physics