物理最新文献

{"title":"Ultra-cold neutron simulation framework for the free neutron lifetime experiment (tau )SPECT","authors":"J. Auler,&nbsp;U. Bajpai,&nbsp;M. Engler,&nbsp;V. Ermuth,&nbsp;M. Fertl,&nbsp;K. Franz,&nbsp;W. Heil,&nbsp;S. Kaufmann,&nbsp;B. Lauss,&nbsp;N. Pfeifer,&nbsp;D. Ries,&nbsp;S. Vanneste,&nbsp;N. Yazdandoost","doi":"10.1140/epja/s10050-025-01673-8","DOIUrl":"10.1140/epja/s10050-025-01673-8","url":null,"abstract":"<div><p>The precise determination of the free neutron lifetime is of great significance in modern precision physics. This key observable is linked to the mixing of up and down quarks via the Cabibbo-Kobayashi-Maskawa matrix element <span>(V_{ud})</span>, and the abundance of primordial elements after the Big-Bang Nucleosynthesis. However, the two leading measurement techniques for the neutron lifetime currently yield incompatible results, a discrepancy referred to as the neutron lifetime puzzle. To address the systematic uncertainties arising from neutron interactions with material walls, the <span>(tau )</span>SPECT experiment employs a fully magnetic trap for ultra-cold neutrons (UCNs). UCNs velocities are extremely low-energy neutrons with typical velocities below <span>(8,text {m/s})</span>, which can be manipulated using magnetic fields, gravity, and suitable material guides, whose surface can reflect them at any angle of incidence. To precisely study and characterize UCN behavior during production, guidance, storage, and detection in <span>(tau )</span>SPECT, we have developed a dedicated simulation framework. This framework is built upon the externally developed UCN Monte Carlo software package <span>PENTrack</span> and is enhanced with two companion tools: one for flexible and parametrizable upstream configuration of <span>PENTrack</span> such that the simulation’s input settings can be adjusted to reproduce the experimental observations. The second package is used for analyzing, visualizing, and animating simulation data. The simulation results align well with experimental data obtained with <span>(tau )</span>SPECT at the Paul Scherrer Institute and serve as a powerful resource for identifying systematic uncertainties and guiding future improvements to the current experimental setup.</p></div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 10","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epja/s10050-025-01673-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep-inelastic scattering at TeV energies with LHC muons","authors":"Reinaldo Francener,&nbsp;Victor P. Gonçalves,&nbsp;Felix Kling,&nbsp;Peter Krack,&nbsp;Juan Rojo","doi":"10.1140/epjc/s10052-025-14829-z","DOIUrl":"10.1140/epjc/s10052-025-14829-z","url":null,"abstract":"<div><p>The LHC far-forward experiments FASER and SND@LHC have pioneered the detection of TeV-energy neutrinos produced in hard-scattering proton-proton collisions at the LHC. In addition to neutrinos, an intense flux of TeV-energy muons reaches these detectors, representing a dominant background for both neutrino studies and beyond the Standard Model searches. Here we demonstrate that this forward muon flux enables a comprehensive neutral-current deep-inelastic scattering (DIS) program at FASER with a strong kinematical overlap with the Electron Ion Collider. For the Run 3 luminosity of <span>({mathcal {L}}_{{textrm{pp}}}=250)</span> fb<span>(^{-1},)</span> more than <span>(10^5)</span> inclusive muon DIS events, of which up to <span>(10^4)</span> from charm production, are expected at FASER<span>(nu .)</span> As a representative application, we demonstrate the sensitivity of muon DIS at FASER<span>(nu )</span> to probe the (intrinsic) charm content of the proton at large-<i>x</i>. We also provide predictions for event yields of muon DIS for future FASER runs and for the proposed Forward Physics Facility.\u0000\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14829-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of DC component in complex voltage waveforms from converter stations on defect structure and electrical performance of ZnO varistors","authors":"Tao Song,&nbsp;Xia Zhao,&nbsp;Nianwen Xiang,&nbsp;Peng Kang,&nbsp;Ziming He,&nbsp;Chaoqun Wang,&nbsp;Chenglin Xu","doi":"10.1007/s00339-025-08805-3","DOIUrl":"10.1007/s00339-025-08805-3","url":null,"abstract":"<div><p>In the ultra-high voltage direct current (UHVDC) system, ZnO varistors in converter stations are subjected to complex voltage waveforms comprising superimposed DC voltages and high-order harmonics. Under such conditions, ZnO varistors may endure severe operational condition. This paper conducts aging tests on DC ZnO varistor discs at 135 °C using complex waveforms from the high-potential converter valve side (A₂) under varying DC components, followed by thermal recovery tests on the aged specimens at 135 °C, to investigate the impact of DC components on the defect structure and electrical performance of ZnO varistors.During the tests, changes in electrical properties, defect structures, double Schottky barriers are analyzed. The results suggest that the electrical properties do not worsen monotonically with the increase of the DC component of the A₂ waveform and the phenomenon can be explained by combining the processes of filling the interface states by electrons and migration of metastable ions. This paper extension of the operational voltage to the breakdown region, this work provides novel insights into aging mechanisms of ZnO varistors.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neutrino production in the central dark-matter spikes of active galaxies","authors":"Polina Kivokurtseva","doi":"10.1140/epjc/s10052-025-14848-w","DOIUrl":"10.1140/epjc/s10052-025-14848-w","url":null,"abstract":"<div><p>Recent multi-messenger observations suggest that high-energy neutrinos may be produced close to central black holes in active galaxies. These regions may host dark-matter (DM) spikes, where the concentration of DM particles is very high. Here we explore the contribution of the DM annihilation to the target photons for the neutrino production, proton–photon interactions, estimate the associated neutrino spectrum and figure out possible future tests of this scenario.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14848-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The measurement problem in liquid NMR quantum computers","authors":"O. Jalili,&nbsp;M. Heidari Adl","doi":"10.1140/epjd/s10053-025-01072-0","DOIUrl":"10.1140/epjd/s10053-025-01072-0","url":null,"abstract":"<p>With the quantum state diffusion measurement theory (QSD), the measurement problem in liquid nuclear magnetic resonance (NMR) quantum computers was addressed and then it was shown that due to stochastical fluctuations, the measured magnetic moment value is comparable to noise for long times. Therefore, we suggested that the measurement time should be short to distinguish signal from noise.</p><p>QSD in NMR quantum computers.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"79 10","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-025-01072-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145230501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of differential and total cross sections for scattering of 14.1 MeV neutrons on (^{12})C nuclei","authors":"D. N. Grozdanov,&nbsp;P. S. Prusachenko,&nbsp;N. A. Fedorov,&nbsp;Yu. N. Kopatch,&nbsp;T. Yu. Tretyakova,&nbsp;G. V. Pampushik,&nbsp;A. V. Andreev,&nbsp;V. R. Skoy,&nbsp;C. Hramco,&nbsp;P. G. Filonchik,&nbsp;P. I. Kharlamov,&nbsp;A. L. Barabanov,&nbsp;TANGRA collaboration","doi":"10.1140/epja/s10050-025-01703-5","DOIUrl":"10.1140/epja/s10050-025-01703-5","url":null,"abstract":"<div><p>Differential cross sections of the elastic and inelastic scattering of 14.1 MeV neutrons on <span>(^{12})</span>C for <span>(^{12})</span>C(n,n<span>(_{0,1-4,7})</span>)<span>(^{12})</span>C channels were measured in the framework of the TANGRA project. The experiment was carried out using the tagged neutron method which helped to reduce the background of random coincidences, determine the neutron flux on the target, and determine the energy of scattered neutrons by the time-of-fligh. The total reaction cross sections were calculated by approximating the measured differential cross sections by expansions in Legendre polynomials and then integrating over the entire range of solid angles. The measured values of the differential cross sections are generally in agreement with the experimental data of other authors within the measurement uncertainties. The obtained data for the total partial cross sections for elastic scattering are in agreement within uncertainties with the evaluated data from various nuclear data libraries (ENDF/B-VIII.0, EAF-2010, FENDL-3.1, JEFF-3.3, JENDL-4.0/HE). The cross section for <span>(^{12})</span>C(n,n<span>(_1)</span>)<span>(^{12})</span>C channel is in agreement with the data from FENDL-3.1 and JENDL-4.0/HE. The total experimental cross section for the <span>(^{12})</span>C(n,n<span>(_{2-7})</span>)<span>(^{12})</span>C channels, which lead to the decay of the <span>(^{12})</span>C nucleus into 3<span>(alpha )</span>-particles obtained in the present work in combination with the experimental data of other authors are consistent with similar cross sections evaluated from the ENDF/B-VIII.0 and JEFF-3.3 libraries, but is significantly smaller than the one estimated from the EAF-2010 library. This result may indicate the need to reduce the evaluations of helium production in carbon compounds under the operating conditions of a fusion reactor, previously made based on the EAF library.</p></div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 10","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Background-dependent and classical correspondences between f(Q) and f(T) gravity","authors":"Cheng Wu,&nbsp;Xin Ren,&nbsp;Yuhang Yang,&nbsp;Yu-Min Hu,&nbsp;Emmanuel N. Saridakis","doi":"10.1140/epjc/s10052-025-14822-6","DOIUrl":"10.1140/epjc/s10052-025-14822-6","url":null,"abstract":"<div><p><i>f</i>(<i>Q</i>) and <i>f</i>(<i>T</i>) gravity are based on fundamentally different geometric frameworks, yet they exhibit many similar properties. This article provides a comprehensive summary and comparative analysis of the various theoretical branches of torsional gravity and non-metric gravity, which arise from different choices of affine connection. We identify two types of background-dependent and classical correspondences between these two theories of gravity. The first correspondence is established through their equivalence within the Minkowski spacetime background. To achieve this, we develop the tetrad-spin formulation of <i>f</i>(<i>Q</i>) gravity and derive the corresponding expression for the spin connection. The second correspondence is based on the equivalence of their equations of motion. Utilizing a metric-affine approach, we derive the general affine connection for static and spherically symmetric spacetime in <i>f</i>(<i>Q</i>) gravity and compare its equations of motion with those of <i>f</i>(<i>T</i>) gravity. Among others, our results reveal that, <i>f</i>(<i>T</i>) solutions are not simply a subset of <i>f</i>(<i>Q</i>) solutions; rather, they encompass a complex solution beyond <i>f</i>(<i>Q</i>) gravity in black hole background.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14822-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomic transport coefficients of liquid 3d transition metals: insights from local field corrections","authors":"Addreta Romman,&nbsp;Utshob Bhattacharjee,&nbsp;R. C. Gosh","doi":"10.1007/s00339-025-08904-1","DOIUrl":"10.1007/s00339-025-08904-1","url":null,"abstract":"<div><p>The influence of local field correction functions (LFCFs) within the pseudopotential formalism on the atomic transport of Liquid 3<i>d</i> transition metals has been studied using hard sphere (HS) theories and universal scaling laws (USLs). We have chosen Bretonnet-Silbert (BS) pseudopotential model with 5 distinct LFCFs proposed by Ichimaru-Utsumi (IU), Vashishta-Singwi (VS), Sarkar et al. (S), Taylor (T) and Farid et al. (F) for variation of effective interionic interaction. Effective HS diameter and excess entropy are basic ingredients of this study which have been determined employing variational modified hypernetted chain integral equation theory along with BS model. Calculated results using USLs are found to be more sensitive to applied LFCFs than those obtained by HS theories. Comparing with available studies, this study shows that HS theories provide more reliable results than USLs. For USLs, S-LFCF provides better results than other LFCFs for most of the systems examined.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of TiO2 to the structural and optical properties of 56TeO2–30B2O3–10MgO–4Nd2O3 glass system","authors":"Mohammad Ayman Abuallan,&nbsp;Mohd Hafiz Mohd Zaid,&nbsp;Khamirul Amin Matori,&nbsp;Yazid Yaakob,&nbsp;Ali Jabbar Abed Al-Nidawi,&nbsp;Abdelkader Mohammed Efa","doi":"10.1007/s00339-025-08932-x","DOIUrl":"10.1007/s00339-025-08932-x","url":null,"abstract":"<div><p>This study examined magnesium borotellurite glass systems added with neodymium oxide and titanium especially the elastic, structural, and physical properties. A sequence of neodymium and titanium added magnesium borotellurite glass was produced and expressed using a formula that displays the proportion of each component as following (56-<span>(:y)</span>)TeO₂–30B₂O₃–10MgO–4Nd₂O₃–<i>y</i>TiO₂, with y = 0, 1, 2, 3, and 4 mol%. The density of the Ti-added MBTNd glass was decreased from 4.16 g/cm³ to 4.14 g/cm³ by adding titanium. Besides, molar volume decreased from 30.54 cm³/mol to 29.92 cm³/mol. XRD analysis prove the amorphous state of glasses. The Urbach energy has decreases because of the titanium ion implantation with the highest value of 0.339 eV for the MBTNdTi-4 glass sample. The indirect and direct band gap energies showed a downward trend with increasing TiO₂ content, attaining their minimum values at 2.498 eV for the MBTNdTi-4 glass (indirect transition) and 3.324 eV for the MBTNdTi-3 glass (direct transition). The MBTNdTi-2 glass sample exhibited the strongest PL emission, indicating that this composition provides the optimal TiO₂ concentration for maximizing luminescence efficiency.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145256602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser induced grating spectroscopy measurements of temperature and water vapour in turbulent lean premixed methane-hydrogen-air flames at pressure","authors":"Lee Weller,&nbsp;Anthony Giles,&nbsp;Oussama Chaib,&nbsp;Steve Morris,&nbsp;Benjamin A. O. Williams,&nbsp;Simone Hochgreb","doi":"10.1007/s00340-025-08573-1","DOIUrl":"10.1007/s00340-025-08573-1","url":null,"abstract":"<div>\u0000 \u0000 <p>This study explores the application of Laser-Induced Grating Spectroscopy (LIGS) for non-intrusive measurements of temperature and water vapour concentration in premixed flames of air with blends of hydrogen and methane under high-pressure conditions. Employing a swirl-stabilized burner, the research demonstrates the capabilities of tracer-free LIGS, using thermal and electrostrictive gratings generated by a 1064 nm Nd:YAG laser, to measure local temperatures and water molar fractions. The study also includes an extension of the thermoacoustic model for characteristics LIGS signals, built in order to extract the relative concentration of water vapour from the ratio of second (thermal) to first (electrostrictive) peak magnitudes. Experiments are conducted in non-sooting flames, leveraging a high-pressure optical chamber (HPOC) with pressures up to 3 bar. The study evaluates mixtures of methane and hydrogen (100%, 70%, and 40% CH<span>(_{4})</span>) and identifies key relationships between LIGS signal characteristics, frequency distributions, and combustion dynamics. Results show excellent agreement between measured temperatures and adiabatic flame temperatures, alongside measurements of water vapour molar fractions. The spatial temperature and water vapour maps are related to the complex mixing and recirculation patterns associated with the flame’s shear and recirculation zones. The results establish LIGS as a robust diagnostic tool for combustion analysis, with potential applications in advancing hydrogen-rich energy systems.</p>\u0000 </div>","PeriodicalId":474,"journal":{"name":"Applied Physics B","volume":"131 11","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00340-025-08573-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}