Computer Physics Communications最新文献

{"title":"Self-consistent charging of complex objects in flowing plasma: Implementation and analysis in WarpX","authors":"Ashwyn Sam,&nbsp;Sigrid Elschot","doi":"10.1016/j.cpc.2025.109680","DOIUrl":"10.1016/j.cpc.2025.109680","url":null,"abstract":"<div><div>The charging of conducting bodies in plasma environments is a fundamental process with implications spanning astrophysical, space, and laboratory plasmas. Accurate modeling of this charging process is essential for understanding and predicting the behavior of objects interacting with plasmas. In this study, we present the implementation of a charging algorithm in the open-source particle-in-cell code WarpX, which enables the simulation of charging for arbitrary 3D geometries in a plasma. The algorithm is verified against analytical solutions from orbital motion limited (OML) theory for a sphere in a static plasma and against published numerical results for a CubeSat in a flowing plasma. We investigate the charging of debris in Low Earth Orbit (LEO) conditions, considering both spherical and realistic debris geometries generated using a custom tool. The simulations reveal that the debris surface potential oscillates at the plasma frequency Doppler-shifted into the lab frame, a phenomenon not previously reported. The oscillations are robust to numerical convergence tests and persist for irregular debris geometries. Reduced density simulations suggest a critical threshold below which the oscillations disappear. Contrary to some earlier studies, precursor solitons do not form in our realistic LEO simulations, even with self-consistent charging of irregular debris. This study demonstrates WarpX's new capabilities for high-fidelity simulations of object charging in plasmas and highlights the complex nature of plasma-object interactions. The insights gained can inform the development of debris detection and mitigation strategies, while the WarpX code provides a valuable tool for future research in this field.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109680"},"PeriodicalIF":7.2,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144115067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel THINC scheme-based CLSVOF method for axisymmetric two-phase flows","authors":"Orkodip Mookherjee ,&nbsp;Shantanu Pramanik ,&nbsp;Atul Sharma","doi":"10.1016/j.cpc.2025.109673","DOIUrl":"10.1016/j.cpc.2025.109673","url":null,"abstract":"<div><div>This paper is on proposition of a THINC (Tangent of the Hyperbola for INterface Capturing) scheme in axisymmetric coordinate system for an algebraic Coupled Level Set and Volume of Fluid (CLSVOF) method-based simulation of two-phase flows. Novelty of the present work lies in consideration of two separate characteristic Heaviside functions in radial and axial directions. Such an approach is shown to yield two distinct forms of direct analytical expression for the advection fluxes of volume fraction in both directions unlike the identical forms used in the existing THINC schemes for Cartesian coordinates. Effectiveness of the proposed CLSVOF method is presented on various axisymmetric advection tests, where it is observed that the present axisymmetric THINC scheme is capable of conserving the volume fraction field up to machine precision level while maintaining the desired interface thickness without any adverse distortions. To ascertain the behavior of this novel scheme for practical problems, a comprehensive validation study is performed for sufficiently different two-phase flows like static droplet, droplet oscillations, droplet fall, bubble rise, and droplet coalescence. It has been demonstrated that the proposed algebraic CLSVOF method emulates the robustness and accuracy of the standard geometric CLSVOF methods, thus facilitating a straightforward approach to numerical implementation in practical scenarios.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109673"},"PeriodicalIF":7.2,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144124212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple spatio-temporal attention network: A deep convolutional network for spatio-temporal evolution prediction of flow fields","authors":"Hongyuan Men ,&nbsp;Ji Zhang ,&nbsp;Yixuan Mao ,&nbsp;Xinliang Li ,&nbsp;Guoan Zhao ,&nbsp;Hongwei Liu","doi":"10.1016/j.cpc.2025.109685","DOIUrl":"10.1016/j.cpc.2025.109685","url":null,"abstract":"<div><div>The recent rapid development of machine learning has promoted its application in turbulence research. This paper presents a Multiple Spatio-Temporal Attention (MSTA) Network to predict the spatio-temporal evolution of multi-variable, multi-timestep turbulent flow fields. The model adopts a complete convolutional architecture instead of a recurrent structure typical of traditional time series models. Nonetheless, the model shows the ability to capture the temporal features of turbulence and form complex nonlinear relationships, thereby predicting the spatio-temporal evolution of turbulent flow fields both accurately and quickly. To improve the model’s prediction accuracy, we propose a novel channel attention mechanism, called Multiple Fusion Attention (MFA), which is designed to capture and fuse channel features at different positions more effectively. Additionally, a Spatial Transform Gradient Sharpening (STGS) method is proposed to constrain the spatial gradient in non-uniform curvilinear grids accurately. Based on the direct numerical simulations (DNS) results of a Mach 6, 34° compression ramp flow, two datasets of different sizes are established and related experiments are designed to validate the effectiveness of the proposed MSTA Network. The experimental comparison and analysis demonstrated the best performance in terms of accuracy and efficiency in the present comparison with other machine-learning models. Besides, a series of experiments considering different sample numbers, dataset sizes, prediction lengths, etc., also confirmed the robustness in various application scenarios. Finally, an extended experiment of the model was conducted on the HyTRV dataset from AeroFlowData under flow conditions of Mach 6 and 0° angle of attack, further demonstrating the model’s universality in diverse conditions.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"315 ","pages":"Article 109685"},"PeriodicalIF":7.2,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A higher-order finite-element implementation of the nonlinear Fokker–Planck collision operator for charged particle collisions in a low density plasma","authors":"M.R. Hardman ,&nbsp;M. Abazorius ,&nbsp;J. Omotani ,&nbsp;M. Barnes ,&nbsp;S.L. Newton ,&nbsp;J.W.S. Cook ,&nbsp;P.E. Farrell ,&nbsp;F.I. Parra","doi":"10.1016/j.cpc.2025.109675","DOIUrl":"10.1016/j.cpc.2025.109675","url":null,"abstract":"<div><div>Collisions between particles in a low density plasma are described by the Fokker–Planck collision operator. In applications, this nonlinear integro-differential operator is often approximated by linearised or ad-hoc model operators due to computational cost and complexity. In this work, we present an implementation of the nonlinear Fokker–Planck collision operator written in terms of Rosenbluth potentials in the Rosenbluth–MacDonald–Judd (RMJ) form. The Rosenbluth potentials may be obtained either by direct integration or by solving partial differential equations (PDEs) similar to Poisson's equation: we optimise for performance and scalability by using sparse matrices to solve the relevant PDEs. We represent the distribution function using a tensor-product continuous-Galerkin finite-element representation and we derive and describe the implementation of the weak form of the collision operator. We present tests demonstrating a successful implementation using an explicit time integrator and we comment on the speed and accuracy of the operator. Finally, we speculate on the potential for applications in the current and next generation of kinetic plasma models.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109675"},"PeriodicalIF":7.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing growth precursor diffusion lengths by inter-surface diffusion","authors":"Stoffel D. Janssens ,&nbsp;Francisco S. Forte Neto ,&nbsp;David Vázquez-Cortés ,&nbsp;Fernando P. Duda ,&nbsp;Eliot Fried","doi":"10.1016/j.cpc.2025.109671","DOIUrl":"10.1016/j.cpc.2025.109671","url":null,"abstract":"<div><div>Understanding and optimizing thin-film synthesis requires measuring the diffusion length <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> of adsorbed growth precursors. Despite technological advances, in-situ measurements of <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> are often unachievable due to harsh deposition conditions, such as high temperatures or reactive environments. In this paper, we propose a fitting approach to determine <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> from experimental data by leveraging inter-surface diffusion between a substrate and a strip obtained by, for example, processing a film. The substrate serves as a source or sink of precursors, which influences the growth dynamics and shapes the strip profile. By fitting simulated profiles to given profiles, we demonstrate that <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> can be determined. To achieve this, we develop a theoretical growth model and a simulation strategy. The growth model incorporates inter-surface diffusion, adsorption, and desorption of growth precursors, with growth being proportional to the concentration of adsorbed precursors. In our simulations, a chain of nodes represents a profile, and growth is captured by the displacement of those nodes, while keeping the node density approximately constant. For strips significantly wider than <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span>, a dimensionless precursor concentration and <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> are the fitting parameters that are determined by optimizing a suitably defined measure of the similarity between simulated and given profiles. We examine how variations in model parameters influence growth dynamics. We also evaluate the robustness of our procedure by analyzing the effect of profile resolution and noise on the fitted parameters. Our approach can offer valuable insights into thin-film growth processes, such as those occurring during plasma-enhanced chemical vapor deposition.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109671"},"PeriodicalIF":7.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"gSeaGen code by KM3NeT: An efficient tool to propagate muons simulated with CORSIKA","authors":"S. Aiello ,&nbsp;A. Albert ,&nbsp;A.R. Alhebsi ,&nbsp;M. Alshamsi ,&nbsp;S. Alves Garre ,&nbsp;A. Ambrosone ,&nbsp;F. Ameli ,&nbsp;M. Andre ,&nbsp;L. Aphecetche ,&nbsp;M. Ardid ,&nbsp;S. Ardid ,&nbsp;H. Atmani ,&nbsp;J. Aublin ,&nbsp;F. Badaracco ,&nbsp;L. Bailly-Salins ,&nbsp;Z. Bardačová ,&nbsp;B. Baret ,&nbsp;A. Bariego-Quintana ,&nbsp;Y. Becherini ,&nbsp;M. Bendahman ,&nbsp;N. Zywucka","doi":"10.1016/j.cpc.2025.109660","DOIUrl":"10.1016/j.cpc.2025.109660","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The KM3NeT Collaboration has tackled a common challenge faced by the astroparticle physics community, namely adapting the experiment-specific simulation software to work with the CORSIKA air shower simulation output. The proposed solution is an extension of the open source code gSeaGen, which allows the transport of muons generated by CORSIKA to a detector of any size at an arbitrary depth. The gSeaGen code was not only extended in terms of functionality but also underwent a thorough redesign of the muon propagation routine, resulting in a more accurate and efficient simulation. This paper presents the capabilities of the new gSeaGen code as well as prospects for further developments.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Program summary&lt;/h3&gt;&lt;div&gt;&lt;em&gt;Program title:&lt;/em&gt; gSeaGen&lt;/div&gt;&lt;div&gt;&lt;em&gt;CPC Library link to program files:&lt;/em&gt; &lt;span&gt;&lt;span&gt;https://doi.org/10.17632/ymgxvy2br4.2&lt;/span&gt;&lt;svg&gt;&lt;path&gt;&lt;/path&gt;&lt;/svg&gt;&lt;/span&gt;&lt;/div&gt;&lt;div&gt;&lt;em&gt;Developer's respository link:&lt;/em&gt; &lt;span&gt;&lt;span&gt;git.km3net.de/opensource/gseagen&lt;/span&gt;&lt;svg&gt;&lt;path&gt;&lt;/path&gt;&lt;/svg&gt;&lt;/span&gt;&lt;/div&gt;&lt;div&gt;&lt;em&gt;Licensing provisions:&lt;/em&gt; BSD 3-Clause&lt;/div&gt;&lt;div&gt;&lt;em&gt;Programming language:&lt;/em&gt; C++&lt;/div&gt;&lt;div&gt;&lt;em&gt;Nature of problem:&lt;/em&gt; Integration of the state-of-the-art extensive air shower Monte Carlo event generator CORSIKA &lt;span&gt;&lt;span&gt;[1]&lt;/span&gt;&lt;/span&gt; into the atmospheric muon simulation for water Cherenkov neutrino telescopes. The primary use case considered is the KM3NeT experiment &lt;span&gt;&lt;span&gt;[2]&lt;/span&gt;&lt;/span&gt;, however, the code should be able to cover other similar experiments as well. The challenges in this work included interfacing the CORSIKA binary output, efficient handling of already generated events to reduce the overall computational cost, and preserving all the additional available information, which can be invaluable in physics analyses.&lt;/div&gt;&lt;div&gt;&lt;em&gt;Solution method:&lt;/em&gt; The readout of CORSIKA simulation was adapted from the base script provided together with CORSIKA and implemented as a standalone flux driver in gSeaGen. The propagation routine has been redesigned to support the geometry of extensive air shower simulations and to improve its efficiency in propagating particles to the detector. To ensure a reliable modelling of muon energy loss and scattering, PROPOSAL &lt;span&gt;&lt;span&gt;[3]&lt;/span&gt;&lt;/span&gt; was set as the default internal code for muon transport. PROPOSAL is an open-source software developed and maintained by the IceCube collaboration &lt;span&gt;&lt;span&gt;[4]&lt;/span&gt;&lt;/span&gt; and is a well-established solution used by the neutrino physics community.&lt;/div&gt;&lt;div&gt;&lt;em&gt;Additional comments including restrictions and unusual features:&lt;/em&gt; The code was tested with GENIE &lt;span&gt;&lt;span&gt;[5]&lt;/span&gt;&lt;/span&gt; version 3.4.0 and PROPOSAL 6.1.5. Currently, linking of gSeaGen to GENIE is mandatory, even in the case of a muon-only simulation using CORSIKA.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;References&lt;/h3&gt;&lt;div&gt;&lt;ul&gt;&lt;li&gt;&lt;span&gt;[1]&lt;/span&gt;&lt;span&gt;&lt;div&gt;D. Heck et al., FZKA-6019 (1998).&lt;/div&gt;&lt;/span&gt;&lt;/li&gt;&lt;li&gt;&lt;span&gt;[2]&lt;/span&gt;&lt;span&gt;&lt;div&gt;S. A","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109660"},"PeriodicalIF":7.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144115068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Toolkit for solving the Optical Bloch Rate Equations in alkali metal atoms based on the QuantumOptics.jl package in Julia","authors":"Dace Osite,&nbsp;Marcis Auzinsh,&nbsp;Laima Busaite,&nbsp;Florian Gahbauer,&nbsp;Arturs Mozers","doi":"10.1016/j.cpc.2025.109678","DOIUrl":"10.1016/j.cpc.2025.109678","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The Optical Bloch Equations (OBEs) are useful for calculating the evolution of the density matrix of an atomic ensemble under the action of some Hamiltonian. A common situation concerns atoms with hyperfine structure that interact with an external magnetic field and laser radiation. When the spectral linewidth of the laser radiation is much larger than the natural linewidth of the transition, the mode spacing is much smaller than the natural linewidth, and the spectral linewidth is much larger than the characteristic evolution time of the density matrix, the OBEs can be reduced to rate equations for Zeeman coherences. We present a toolkit for solving these rate equations based on the &lt;span&gt;QuantumOptics.jl&lt;/span&gt; package in the Julia language. Using these tools makes the code much more readable than previous implementations in C/C++, but almost as fast and easier to parallelize. The toolkit includes functions for calculating the steady-state solution of density matrix of alkali metal atoms in the presence of an external magnetic field and exposed to a pump laser beam of arbitrary polarization and propagation direction. Based on this density matrix, the toolkit offers functions to determine the fluorescence intensity of arbitrary polarization and direction as well as the absorption of a weak probe beam, also of arbitrary polarization and propagation direction. It can also produce a plot of the electronic angular momentum distribution of the atom based on the calculated density matrix. The toolkit is available on Github and has been validated by comparing its results to legacy code written in C/C++ and experimental measurements. As a test case, we show how the toolkit can be used to optimize a simple atomic magnetometer.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Program summary&lt;/h3&gt;&lt;div&gt;&lt;em&gt;Program Title:&lt;/em&gt; OpticalBlochEquations.jl&lt;/div&gt;&lt;div&gt;&lt;em&gt;CPC Library link to program files:&lt;/em&gt; &lt;span&gt;&lt;span&gt;https://doi.org/10.17632/bbjh8bdcgj.1&lt;/span&gt;&lt;svg&gt;&lt;path&gt;&lt;/path&gt;&lt;/svg&gt;&lt;/span&gt;&lt;/div&gt;&lt;div&gt;&lt;em&gt;Licensing provisions:&lt;/em&gt; MIT&lt;/div&gt;&lt;div&gt;&lt;em&gt;Programming language:&lt;/em&gt; Julia&lt;/div&gt;&lt;div&gt;&lt;em&gt;Supplementary material:&lt;/em&gt; GitHub floriansLU/OpticalBlochEquations.jl&lt;/div&gt;&lt;div&gt;&lt;em&gt;Nature of problem:&lt;/em&gt; Interaction of alkali atoms with radiation and magnetic fields.&lt;/div&gt;&lt;div&gt;&lt;em&gt;Solution method:&lt;/em&gt; Numerically solving the Optical Bloch Rate Equations in steady-state conditions.&lt;/div&gt;&lt;div&gt;&lt;em&gt;Additional comments including restrictions and unusual features:&lt;/em&gt; The framework is based on the &lt;span&gt;QuantumOptics.jl&lt;/span&gt; package and calculates fluorescence of a pump beam or absorption of a probe beam in an atomic ensemble in the presence of an external magnetic field.&lt;/div&gt;&lt;div&gt;The program solves not the full Optical Bloch Equations, but the restricted case when they can be reduced to rate equations for Zeeman coherences, which is possible under the following conditions:&lt;ul&gt;&lt;li&gt;&lt;span&gt;•&lt;/span&gt;&lt;span&gt;&lt;div&gt;the spectral linewidth of the laser radiation Δ&lt;em&gt;ω&lt;/em&gt; is much larger th","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109678"},"PeriodicalIF":7.2,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144099416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of the shifted minimal residual method for multiply shifted linear systems with real symmetric or complex Hermitian coefficient matrices","authors":"Shuntaro Hidaka ,&nbsp;Shuhei Kudo ,&nbsp;Takeo Hoshi ,&nbsp;Yusaku Yamamoto","doi":"10.1016/j.cpc.2025.109679","DOIUrl":"10.1016/j.cpc.2025.109679","url":null,"abstract":"<div><div>We consider solving multiply shifted linear systems <span><math><mo>(</mo><mi>A</mi><mo>+</mo><msup><mrow><mi>σ</mi></mrow><mrow><mo>(</mo><mi>m</mi><mo>)</mo></mrow></msup><mi>I</mi><mo>)</mo><msup><mrow><mi>x</mi></mrow><mrow><mo>(</mo><mi>m</mi><mo>)</mo></mrow></msup><mo>=</mo><mi>b</mi></math></span> (<span><math><mi>m</mi><mo>=</mo><mn>1</mn><mo>,</mo><mo>…</mo><mo>,</mo><mi>M</mi></math></span>) with a real symmetric or complex Hermitian coefficient matrix <em>A</em>. For this type of problem, the shifted COCG and shifted BiCG methods have been considered as the methods of choice for the real and complex cases, respectively, and they are implemented in matrix libraries such as K<em>ω</em>. While it is also possible to apply the shifted version of the MINRES algorithm, to the best of our knowledge, the approach has attracted less attention. In this paper, we investigate mathematical properties of the shifted MINRES method applied to this type of problem and show that it has several advantages over the shifted COCG or shifted BiCG methods, such as absence of breakdown, monotonic decrease of the residual norm, and a lower operation count in the complex Hermitian case. Numerical results that confirm these advantages are also provided.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109679"},"PeriodicalIF":7.2,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144106890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The coupling coefficients with six parameters and the generalized hypergeometric functions","authors":"S. Özay ,&nbsp;S. Akdemir ,&nbsp;E. Öztekin","doi":"10.1016/j.cpc.2025.109656","DOIUrl":"10.1016/j.cpc.2025.109656","url":null,"abstract":"&lt;div&gt;&lt;div&gt;In this study, the Gaunt coefficients, Clebsch–Gordan coefficients, and the Wigner 3&lt;em&gt;j&lt;/em&gt; and 6&lt;em&gt;j&lt;/em&gt; symbols are expressed as the product of generalized hypergeometric functions with unit argument and a normalization coefficient. By exploiting the symmetry properties of generalized hypergeometric functions, these functions are transformed into numerically computable forms, and the normalization coefficients are fully expressed in terms of binomial coefficients. New mathematical expressions, in the form of a series of products of three Gaunt coefficients, are presented, which can be used to verify the accuracy of numerical calculations.&lt;/div&gt;&lt;div&gt;An algorithm has been developed to compute binomial coefficients and generalized hypergeometric functions using recurrence relations, eliminating the need for factorial functions. Utilizing this algorithm and the derived analytical expressions, the Gaunt_CG_3j_and_6j Mathematica program, which numerically calculates the Gaunt coefficients, Clebsch–Gordan coefficients, and the Wigner 3&lt;em&gt;j&lt;/em&gt; and 6&lt;em&gt;j&lt;/em&gt; symbols, was written without relying on Mathematica’s built-in functions. The program can be easily adapted to other programming languages and run on all versions of Mathematica.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Program Summary&lt;/h3&gt;&lt;div&gt;&lt;em&gt;Program title:&lt;/em&gt; Gaunt_CG_&lt;em&gt;3j_&lt;/em&gt;and_&lt;em&gt;6j&lt;/em&gt;&lt;/div&gt;&lt;div&gt;&lt;em&gt;CPC Library link to program files:&lt;/em&gt; &lt;span&gt;&lt;span&gt;https://doi.org/10.17632/pwhry4278g.1&lt;/span&gt;&lt;svg&gt;&lt;path&gt;&lt;/path&gt;&lt;/svg&gt;&lt;/span&gt;&lt;/div&gt;&lt;div&gt;&lt;em&gt;Licensing provisions:&lt;/em&gt; GPLv2&lt;/div&gt;&lt;div&gt;&lt;em&gt;Programming language&lt;/em&gt;: Wolfram Language (Mathematica 9.0 or higher)&lt;/div&gt;&lt;div&gt;&lt;em&gt;Nature of problem&lt;/em&gt;:&lt;/div&gt;&lt;div&gt;In this study, analytical expressions for the Gaunt coefficients and Wigner 6&lt;em&gt;j&lt;/em&gt; symbols are derived as the product of generalized hypergeometric functions and a normalization coefficient. Analytical expressions for the Wigner 3&lt;em&gt;j&lt;/em&gt; symbols in terms of the Clebsch–Gordan (CG) coefficients are given in the same form in Ref. [&lt;span&gt;&lt;span&gt;27&lt;/span&gt;&lt;/span&gt;]. This study introduces new analytical expressions involving sums to verify the accuracy of numerical calculations for all coupling coefficients with six parameters consolidated into a single formula. The Gaunt_CG_3j_and_6j program numerically calculates the coupling coefficients presented in this study and Ref. [&lt;span&gt;&lt;span&gt;27&lt;/span&gt;&lt;/span&gt;].&lt;/div&gt;&lt;div&gt;&lt;em&gt;Solution method&lt;/em&gt;:&lt;/div&gt;&lt;div&gt;In this study, all coupling coefficients with six parameters are expressed as the product of the generalized hypergeometric function with unit argument and the “&lt;em&gt;normalization&lt;/em&gt;” constant, which is written in terms of binomial coefficients. Therefore, the main structure of our program consists of numerical calculation of the binomial coefficients and generalized hypergeometric functions with unit argument.&lt;/div&gt;&lt;div&gt;In our algorithm, binomial coefficients with parameters containing negative or positive integers are calculated using ","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"315 ","pages":"Article 109656"},"PeriodicalIF":7.2,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-to-one correspondence reconstruction at the electron-positron Higgs factory","authors":"Yuexin Wang ,&nbsp;Hao Liang ,&nbsp;Yongfeng Zhu ,&nbsp;Yuzhi Che ,&nbsp;Xin Xia ,&nbsp;Huilin Qu ,&nbsp;Chen Zhou ,&nbsp;Xuai Zhuang ,&nbsp;Manqi Ruan","doi":"10.1016/j.cpc.2025.109661","DOIUrl":"10.1016/j.cpc.2025.109661","url":null,"abstract":"<div><div>We propose one-to-one correspondence reconstruction for electron-positron Higgs factories. For each visible particle, one-to-one correspondence aims to associate relevant detector hits with only one reconstructed particle and accurately identify its species. To achieve this goal, we develop a novel detector concept featuring 5-dimensional calorimetry that provides spatial, energy, and time measurements for each hit, and a reconstruction framework that combines state-of-the-art particle flow and machine learning algorithms. In the benchmark process of Higgs to di-jets, over 91% of visible energy can be successfully mapped into well-reconstructed particles that not only maintain a one-to-one correspondence relationship but also associate with the correct combination of cluster and track, improving the invariant mass resolution of hadronically decayed Higgs bosons by 25%. Performing simultaneous identification on these well-reconstructed particles, we observe efficiencies of 97% to nearly 100% for charged particles (<span><math><msup><mrow><mi>e</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span>, <span><math><msup><mrow><mi>μ</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span>, <span><math><msup><mrow><mi>π</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span>, <span><math><msup><mrow><mi>K</mi></mrow><mrow><mo>±</mo></mrow></msup></math></span>, <span><math><mi>p</mi><mo>/</mo><mover><mrow><mi>p</mi></mrow><mrow><mo>¯</mo></mrow></mover></math></span>) and photons (<em>γ</em>), and 75% to 80% for neutral hadrons (<span><math><msubsup><mrow><mi>K</mi></mrow><mrow><mi>L</mi></mrow><mrow><mn>0</mn></mrow></msubsup></math></span>, <em>n</em>, <span><math><mover><mrow><mi>n</mi></mrow><mrow><mo>¯</mo></mrow></mover></math></span>). For physics measurements of Higgs to invisible and exotic decays, golden channels to probe new physics, one-to-one correspondence could enhance discovery power by 10% to up to a factor of two. This study demonstrates the necessity and feasibility of one-to-one correspondence reconstruction at electron-positron Higgs factories.</div></div>","PeriodicalId":285,"journal":{"name":"Computer Physics Communications","volume":"314 ","pages":"Article 109661"},"PeriodicalIF":7.2,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144084695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}