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Angularity in Higgs boson decays via H→gg at NNLL'accuracy 认领 引用
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作者 Jiawei Zhu Yujin Song +2 位作者 Jun Gao Daekyoung Kang Tanmay Maji 《Chinese Physics C》 SCIE CAS CSCD 2025年第2期60-80,共21页
We present improved predictions of a class of event-shape distributions called angularity for a contribution from an effective operator in Higgs hadronic decay that suffers from large perturbative uncertainties.In the... We present improved predictions of a class of event-shape distributions called angularity for a contribution from an effective operator in Higgs hadronic decay that suffers from large perturbative uncertainties.In the framework of the soft-collinear effective theory,logarithmic terms of the distribution are resummed at NNLL'accuracy,for which a two-loop constant of gluon-jet function for angularity is independently determined using a fit to the fixed-order distribution at the NLO corresponding to O(as2)relative to the Born rate.Our determination has reasonable agreement with the value in a recently released thesis.In the fit,we use an asymptotic form with a fractional power conjectured from recoil corrections at one-loop order,and it improves the accuracy of determining positive values of the angularity parameter a.The resummed distribution is matched to the NLO fixed-order results to make our predictions valid at all angularity values.We also discuss the first and subtracted moments of angularity as a function of a that enable the extraction of information on leading and subleading nonperturbative corrections associated with gluons. 展开更多
关键词 Higgs decay soft-collinear effective theory angularity resummation
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Mock Observations for the CSST Mission:CPI-C——Instrument Simulation 认领 引用 被引量：1
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作者 Gang Zhao Yiming Zhu +7 位作者 Jiangpei Dou Xi Zhang Yili Chen Zhonghua Lv Bingli Niu Zhaojun Yan Bo Ma Ran Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第2期136-147,共12页
To support the development of the data processing pipeline and the scientific performance assessment for the Cool Planet Imaging Coronagraph(CPI-C)on the Chinese Space Station Survey Telescope,we have developed the en... To support the development of the data processing pipeline and the scientific performance assessment for the Cool Planet Imaging Coronagraph(CPI-C)on the Chinese Space Station Survey Telescope,we have developed the end-to-end instrument simulation program,CPISM.This paper details the core modules of CPISM that simulate the CPI-C instrument,focusing on the simulation of the high-contrast imaging optical system and the visible-band science camera.We modeled key optical components,such as the transmission apodizing filter,the wavefront corrector,and the focal plane mask using the HCIPy package.A 10-8contrast dark hole region,consistent with design specifications,was simulated using the Electric Field Conjugation optimization method,and broadband observation effects were considered.For the science camera,which is an electron multiplying charge-coupled device,we established a detailed model encompassing photon collection,charge transfer,electron multiplication(EM),and readout processes,based on test data.This model simulates complex instrumental features including dark current,charge transfer efficiency,clock-induced charge,multiplication noise factor,and various readout effects like striping and drift.We also proposed and validated an improved statistical model for the EM process to enhance simulation efficiency.CPISM can generate simulated images containing rich instrumental details,closely similar to the expected real observational data,thus laying the foundation for the development and verification of CPI-C data processing algorithms and preparations for future scientific research. 展开更多
关键词 instrumentation high angular resolution-planets and satellites detection-methods numerical
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Achieving high strength and excellent ductility in a Zn-3Cu-1Mg alloy through minor Nd addition and multi-pass ECAP 认领 引用
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作者 Huan Liu Yinyuan Chen +6 位作者 Lifeng Ye Xiaoyu Qin Chao Sun Zhangwei Yang Yuna Wu Jia Ju Wenkai Wang 《Metals Advances》 SCIE EI CAS CSCD 2026年第4期23-33,共11页
Nd element has been extensively investigated in biodegradable magnesium alloys due to its superior strengthening effect and biocompatibility.However,the role of Nd in biodegradable zinc alloys remains poorly understoo... Nd element has been extensively investigated in biodegradable magnesium alloys due to its superior strengthening effect and biocompatibility.However,the role of Nd in biodegradable zinc alloys remains poorly understood.This work elucidates the impact of Nd microalloying(0.3 wt%)on Zn-3Cu-1Mg alloy processed via multi-pass equal channel angular pressing(ECAP).The as-cast alloy exhibited a composite microstructure comprising η-Zn solid solution,CuZn5 phase,lamellar η-Zn/Mg2Zn11eutectic,and petaloid NdZn11 particles.8 pass(8 P)and 12 pass(12 P)ECAP processing induced severe plastic deformation in the alloy,resulting in a refined grain structure through dynamic recrystallization.However,the shape and size of the petal-like NdZn11 phase remain largely unchanged,despite the development of numerous cracks within them.The alloy subjected to 12 P ECAP exhibits exceptional strength-ductility synergy,with yield strength(352 MPa),ultimate tensile strength(402 MPa),and elongation(31.7%)—a mechanical profile which not only meet the performance requirements for degradable metals but also surpass those of existing RE-containing zinc alloys.The significant improvement in strength is attributed to microstructural refinement and heterogeneous deformation strengthening from the alternating arrangement of soft CuZn5 layers and hard eutectic layers.The extensive cracking within the petal-like NdZn11 phase facilitates energy absorption and dissipation during deformation,thereby delaying crack propagation and enhancing the alloy's ductility.This study elucidates the evolution mechanisms of the NdZn11 phase,providing a theoretical foundation for engineering high-performance zinc alloys through rare earth element alloying. 展开更多
关键词 Zn alloy Rare earth element Equal channel angular pressing Microstructure Mechanical properties
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Ultra-high strength−ductility synergetic improvement mechanism in Mg−8Bi−1Al−1Zn alloy by inverse temperature field ECAP processing 认领 引用
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作者 Shuai-ju MENG Jin-long SONG +6 位作者 Jian-jun ZHANG Hao LIU Jin-qi GUI Hui YU Gui-rong YANG Guang-li BI Yuan-dong LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2026年第7期2005-2016,共12页
Aiming at developing Mg alloys with good strength and ductility,an inverse temperature field equal channel angular pressing(ITF-ECAP)technique was proposed to realize the severe plastic processing of Mg−8Bi−1Al−1Zn(BA... Aiming at developing Mg alloys with good strength and ductility,an inverse temperature field equal channel angular pressing(ITF-ECAP)technique was proposed to realize the severe plastic processing of Mg−8Bi−1Al−1Zn(BAZ811,wt.%)alloy at low temperature of~80°C.As a result,a microstructure consisting of ultrafine grains having an average grain size(AGS)of~506 nm and fine grains with an AGS of~1.36μm was constructed in BAZ811 alloy through 4-pass ITF-ECAP processing.Additionally,a large amount of nano-sized Mg3Bi2 phase precipitated during ITF-ECAP processing,and the micro-scale Mg3Bi2 particles were greatly refined.Furthermore,the ITF-ECAPed BAZ811 alloy exhibits an ultra-high strength−ductility synergy with yield strength and elongation of(381.5±4.2)MPa and(21.4±1.6)%,respectively.High strength stems from grain boundary,precipitate,and dislocation strengthening;good ductility arises from high intergranular strain coordination and weak texture plasticization. 展开更多
关键词 Mg−Bi alloy equal channel angular pressing microstructure mechanical properties
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Thermodynamic real-time coupling modeling and thermal characteristic analysis of angular contact ball bearings under combined loads 认领 引用
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作者 Wenbing Tu Yuankuo Lou +1 位作者 Chenlu Liu Wennian Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第5期518-534,共17页
The distribution of heat generation and operating temperature are crucial factors affecting the performance and useful service life of angular contact ball bearings.A thermodynamic real-time coupling analytical model ... The distribution of heat generation and operating temperature are crucial factors affecting the performance and useful service life of angular contact ball bearings.A thermodynamic real-time coupling analytical model is established in this work to illustrate alterations in the bearing structure,internal load,and the sliding and rotation of the ball correlated with temperature fluctuations.The temperature rise and heat generation of angular contact ball bearings under combined loads are accurately calculated.The simulation of the temperature rise in bearings is conducted based on this model,and the effectiveness of the model is validated through simulation experiments.The simulation results of the distribution of heat generation are compared between thermodynamic real-time coupling and thermodynamic sequential coupling,with a focus on the transient thermal characteristics of bearings and the effect of load on their steady-state thermal characteristics.The precision of temperature simulation through thermodynamic real-time coupling is significantly higher than that through thermodynamic sequential coupling.Axial load mainly affects heat generated by the sliding and rotation of the ball on the inner raceway,while radial load predominantly affects the heat generation of the ball due to sliding on the inner and outer raceways.The findings of the work can guide the design and performance evaluation of angular contact ball bearings and provide support for temperature simulation. 展开更多
关键词 Angular contact ball bearings Combined loads Thermodynamic real-time coupling Thermal characteristics
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Single-shot reconstruction of high-dimensional complex orbital angular momentum spectrum under system misalignment 认领 引用
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作者 Xiao Wang Shupeng Zhao +5 位作者 Zhuhe Jing Ruifeng Liu Yongchang Zhang Pei Zhang a Hong Gao Fuli Li 《Advanced Photonics Nexus》 CSCD 2026年第3期160-166,共7页
The detection of orbital angular momentum(OAM)is fundamental for advancing various applications involving vortex beams.Current measurement methodologies face challenges such as inefficiencies,complex system configurat... The detection of orbital angular momentum(OAM)is fundamental for advancing various applications involving vortex beams.Current measurement methodologies face challenges such as inefficiencies,complex system configurations,and the requirement for high interference stability.The notable challenges of OAM reconstruction are system misalignment and single-shot measurement.We propose a model-driven artificial neural network approach to reconstruct high-dimensional complex OAM spectra from single-shot diffraction intensity measurement under system misalignment,eliminating the need for extensive experimental data for training.Our approach may advance OAM-based high-dimensional information encoding and optical communication while also fostering further exploration at the intersection of physical models and neural networks. 展开更多
关键词 orbital angular momentum single-shot measurement machine learning
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Research on error performance of underwater OAM multiplexing optical communication assisted by deep learning 认领 引用
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作者 Aiping HUANG Yi CAO +1 位作者 Honglin WANG Linwei TAO 《Optoelectronics Letters》 EI 2026年第5期261-267,共7页
In this paper,a novel convolutional neural network(CNN)assisted decoding method is proposed to recover information directly for underwater orbital angular momentum(OAM)multiplexing optical communication.The effects of... In this paper,a novel convolutional neural network(CNN)assisted decoding method is proposed to recover information directly for underwater orbital angular momentum(OAM)multiplexing optical communication.The effects of various attenuations and ocean water types,such as absorption,scattering,turbulence fading,noise and diffraction,are considered comprehensively in our analysis.A regularly spaced continuous phase screen is used to represent ocean turbulence.And the angular diffraction function is exploited for simulating the propagation of the OAM beams.In order to minimize the bit error rate(BER)and simplify the receiver design,a CNN assisted decoding method is used to compensate the distorted OAM light and decode the transmission data directly without channel estimation and equalization.The CNN is trained to learn the multiplexed OAM light intensity map generated under various water environments.The bit error performance of CNN OAM system is also compared with that of traditional Gerchberg-Saxton(GS)algorithm.Our numerical simulation results indicate that the CNN assisted method combats the impairing effects of fading and improves the underwater OAM system performance obviously.Furthermore,it outperforms GS algorithm in almost all the turbulence environments at the same water environment.And the BER of the CNN assisted system still decreases effectively by increasing signal-to-noise ratio(SNR)even in moderate and strong turbulence situations while at the same time requiring less computation complexity. 展开更多
关键词 angular diffraction function underwater orbital angular recover information directly regularly spaced continuous phase screen Convolutional Neural Network CNN Deep Learning convolutional neural network cnn assisted Underwater Optical Communication
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CPI-C:Cool Planet Imaging Coronagraph on Chinese Space Station Survey Telescope 认领 引用
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作者 Jiang-Pei Dou Xi Zhang +23 位作者 Gang Zhao Ming-Ming Xu Zhen Wu Gang Wang Bao-Ning Yuan Ling-Yi Kong Yi-Ming Zhu Bingli Niu Zhong-Hua Lv Yong-Jun Qi Shu Jiang Bo Chen Wei Guo Di Wang Ying-Lu Lin Li-Ping Zheng Jing Guo Ruo-Kun Li Li-Yan Xu Hui-Hai Wu Cheng Wen Shu-Wei Miao Bo-Yang Lv Wei-Miao Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第5期275-301,共27页
Cool Planet Imaging Coronagraph(CPI-C)on Chinese Space Station Survey Telescope is proposed to direct image the cool planets around nearby solar-type stars(within 40 pc).The core scientific objective of CPI-C is to co... Cool Planet Imaging Coronagraph(CPI-C)on Chinese Space Station Survey Telescope is proposed to direct image the cool planets around nearby solar-type stars(within 40 pc).The core scientific objective of CPI-C is to conduct high-contrast directly imaging surveys of exoplanets ranging in size from Neptune-like to Jupiter-like,located at separations of 0.5–5 au from their host stars,and to perform systematic spectroscopic analysis of the detected planets through high-precision multi-band photometry.CPI-C employs a step-transmission apodization technique to suppress the diffraction noises from the telescope pupil and a precise phase correction technique to eliminate the speckle noises due to imperfections of the optical surfaces.The contrast requirement is better than 10−8 at an inner working angle of 3–4λ/D,in the visible wavelength from 600 to 900 nm.CPI-C will be the first space-based instrument capable of directly imaging the reflection light from the cool exoplanets in the visible wavelength enabling the measurement of key physical parameters such as the effective temperature,surface gravity,radius,mass,and other key parameters.The potential observation results will significantly contribute to further understand the formation and evolution mechanisms of planets,which will also lay a solid foundation for future confirmation of the Earth-twins in the next generation space flagship missions. 展开更多
关键词 space vehicles instruments-instrumentation adaptive optics-techniques high angular resolution-planets and satellites general-planets and satellites detection-planets and satellites atmospheres-planets and satellites gaseous planets-techniques image processing
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Investigation of Oil-air Two-Phase Flow Inside Angular Contact Ball Bearing with Textured Cage 认领 引用
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作者 WANG Baomin FANG Wenbo +1 位作者 YAN Ruixiang QIAN Sikai 《Journal of Shanghai Jiaotong university(Science)》 EI 2026年第2期528-536,共9页
Surface texture technology is a method to improve the tribological properties of friction pairs.In this study,a cylindrical texture is designed in cage pocket,and then the volume of fluid model and the multireference ... Surface texture technology is a method to improve the tribological properties of friction pairs.In this study,a cylindrical texture is designed in cage pocket,and then the volume of fluid model and the multireference frame method are used to investigate the oil volume fraction inside the bearing cavity,the pressure and oil distribution on the ball surface,and the oil distribution on the inner/outer raceway.The results show that the cylindrical texture in cage pocket is helpful to increase the oil volume fraction inside the bearing cavity,improve the pressure distribution on the ball surface,and increase the oil content on the ball surface.The cage pocket texture helps the ball to carry more lubrication oil in the high-speed rotation process,which increases the oil content of the outer raceway and improves the oil-air lubrication effect of the ball.This study proposes a new texture arrangement in cage pocket of angular contact ball bearings,and introduces the mixed mesh method to divide the fluid domain of bearing.Through comparative study,the cage pocket texture is helpful to improve the oil-air lubrication efficiency. 展开更多
关键词 angular contact ball bearing surface texture cage air-liquid two-phase flow
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Low-Cycle Fatigue Behavior of Ultrafine-Grained Pure Titanium 认领 引用
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作者 Liu Xiaoyan Wang Zixuan +2 位作者 Yang Xirong Luo Lei Wang Jingzhong 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2026年第5期1191-1198,共8页
Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(... Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(CG)pure titanium were conducted by Instron electro-hydraulic servo fatigue testing machine in the strain amplitude range of 0.5%—1.1%at room temperature.Transmission electron microscope(TEM)and scanning electron microscope were used to investigate the microstructure and fracture surface of UFG pure titanium after fatigue tests.Results show that UFG pure titanium exhibits a longer low-cycle fatigue life,compared with the CG pure titanium.For example,at a total strain amplitude of 0.5%,UFG and CG pure titanium has fatigue life of 10850 and 4820 cycles,respectively.Significant cyclic softening occurs in UFG pure titanium,except in the case of a total strain amplitude of 0.5%.Hysteresis loop area is increased rapidly with the increase in strain amplitude.The fracture surface shows that the fatigue crack is initiated from the specimen surface.A series of fatigue striations and many microcracks exist in the propagation region.With the increase in strain amplitude,the predominant failure mode is transformed from ductile failure into quasi-cleavage failure.Dislocation slip is the main plastic deformation mechanism of UFG pure titanium during low-cycle fatigue deformation. 展开更多
关键词 ultrafine-grained pure titanium equal channel angular pressing+rotatory swaging low-cycle fatigue dislocation slip
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Angular momentum distribution of atomic hydrogen in excited states under ultra-short laser field 认领 引用
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作者 Zhaoyan Zhou Dongwen Zhang Zengxiu Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第3期265-270,共6页
We investigate the population distribution of excited angular momentum(l)states in the interaction between a hydrogen atom and an ultra-short laser pulse.Through numerical solution of the time-dependent Schröding... We investigate the population distribution of excited angular momentum(l)states in the interaction between a hydrogen atom and an ultra-short laser pulse.Through numerical solution of the time-dependent Schrödinger equation,we theoretically investigate the laser-induced oscillations among excited l-states.Temporal evolution analysis reveals distinctive signatures of both multiphoton excitation and frustrated tunneling ionization processes.Specifically,multiphoton excitation dominates during the final optical cycle as the laser peak intensity attenuates,thereby critically determining the final l-states population distribution.We demonstrate that the angular quantum states'parity effect does not persist,even for ultra-short pulses with broad frequency bandwidths.The parity effect is also unaffected by laser field asymmetry. 展开更多
关键词 ultra-short laser pulses excited angular momentum states time-dependent Schr¨odinger equation parity effect
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Polygonal generalized perfect spatiotemporal optical vortices 认领 引用
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作者 Shuoshuo Zhang Zhangyu Zhou +6 位作者 Qianyi Wei Zhongsheng Man Changjun Min Wending Zhang Yuquan Zhang Ting Mei Xiaocong Yuan 《Opto-Electronic Science》 CAS 2026年第3期1-11,共11页
Recently,perfect spatiotemporal optical vortices(PSTOVs)have attracted significant attention due to their topological-charge-independent radius and their ability to carry transverse orbital angular momentum.However,ex... Recently,perfect spatiotemporal optical vortices(PSTOVs)have attracted significant attention due to their topological-charge-independent radius and their ability to carry transverse orbital angular momentum.However,existing studies on PSTOVs remain largely restricted to the simplest annular intensity profiles,limiting their versatility in tailoring light-matter interactions.Extending PSTOVs toward programmable distributions is therefore highly desirable for both fundamental studies and practical applications.To fill this research gap,we propose the concept of generalized perfect spatiotemporal optical vortices(GPSTOVs),whose intensity profiles can be flexibly engineered while preserving their intrinsic"perfect"properties.Unlike previous complex-amplitude modulation approaches,GPSTOV pulses are generated via a pure-phase modulation scheme,enabling higher modulation efficiency and improved energy utilization.By encoding a shape-controllable digital axicon and a vortex phase in the spatiotemporal frequency domain,we experimentally realize a family of polygonal GPSTOV pulses with tunable geometries.The measured spatiotemporal profiles agree well with theoretical predictions.Our results expand the scope of PSTOV research and hold promises for applications in optical communications,particle manipulation,and other fields requiring precise spatiotemporal control of ultrafast light pulses. 展开更多
关键词 spatiotemporally structured light transverse orbital angular momentum generalized perfect spatiotemporal optical vortices pure-phase modulation
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Full Analysis of CP Violation Induced by the Decay Angular Correlations in Four-Body Cascade Decays of Heavy Hadrons 认领 引用
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作者 Zhen-Hua Zhang Jian-Yu Yang Xin-Heng Guo 《Chinese Physics Letters》 SCIE EI CAS CSCD 2026年第7期12-16,I0003-I0005,共5页
The violation of the charge-parity(CP)transformation symmetry,which has been observed in numerous pure meson decay processes,was only confirmed very recently by the LHCb collaboration in the four-body decay of the hea... The violation of the charge-parity(CP)transformation symmetry,which has been observed in numerous pure meson decay processes,was only confirmed very recently by the LHCb collaboration in the four-body decay of the heavy baryonΛb0,Λb0→pK−π+π−,through a comparison of the decay branching ratio with that of the CP-conjugate process.However,the detailed dynamics behind this CP asymme-try is obviously far from clear.We propose a formalism for the full analysis of the decay angular correlations in four-body cascade decays of heavy hadrons which can provide more information about the CP violation in these decays.To illustrate this,we apply the decay angular correlation analysis of CP violation to another four-body decay channel that involves baryons,B0→ppK+π−,which has also been investigated by the LHCb collaboration with no evidence of CP violation being found.Surprisingly,based on a simple assumption on the statistical errors,and with the event yield extracted inversely from the published data of LHCb,we obtain non-zero CP asymme-tries of about 10%corresponding to the decay angular correlations,which are considerably larger than the CP asymmetries observed in theΛb0→pK−π+π−channel.We recommend that experimental collaborations conduct comprehensive decay angular correlation analyses of CP violation in four-body decays of heavy hadrons,including the two channels discussed above. 展开更多
关键词 lhcb collaboration CP violation four body decays heavy baryon b b pk comparison decay branching ratio angular correlations heavy hadrons pure meson decay processeswas
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Deformed shell gap near N~100 for Gd and Dy nuclei 认领 引用
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作者 S.K.Ghorui A.Ghosh 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第3期166-175,共10页
The structures of even-even Gd and Dy isotopes around N=100 were investigated using a fully self-consistent microscopic model.The systematics of the exited 21+and 41+energies reveal a peak-like structure a... The structures of even-even Gd and Dy isotopes around N=100 were investigated using a fully self-consistent microscopic model.The systematics of the exited 21+and 41+energies reveal a peak-like structure at N=100 along the Gd(Z=64)and Dy(Z=66)isotopic chains.This supports the evidence for a subshell gap near N=100.The nuclear structure properties studied are important to understand the r-process elemental abundance peak at A~160. 展开更多
关键词 Nuclear structure Deformed shell gap Deformed Hartree–Fock Angular momentum projection EM transition
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Selective Actuator Adjustment Method Based on Mixed-integer Nonlinear Programming and Heuristic Genetic Algorithm for Radiation Pattern Optimization of Leighton Chajnantor Telescope 认领 引用
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作者 Jia You Zheng Wang +2 位作者 Long Cheng Run-Fu Peng Yong Bi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第3期204-218,共15页
The primary reflector of the Leighton Chajnantor Telescope is usually affected by various environmental loads and panel misalignments,both of which can significantly degrade its radiation pattern performances.To addre... The primary reflector of the Leighton Chajnantor Telescope is usually affected by various environmental loads and panel misalignments,both of which can significantly degrade its radiation pattern performances.To address these effects,this paper focuses on optimizing actuator adjustments and proposes a Mixed-integer Nonlinear Programming model that takes key radiation pattern performance indicators as the optimization objective.Recognizing the limitations of traditional optimization methods,which are prone to falling into local optima due to high-dimensional and complex nonlinear constraints,and struggle to optimize both actuator positions and adjustment values simultaneously,we introduce an enhanced genetic algorithm combined with a heuristic actuator selection rule,which efficiently solves the beam performance optimization problem by regulating part of the actuators.Notably,the approach demonstrates a significant reduction in the magnitude of the pointing deviation,achieving approximately 80%of decrease when utilizing 20 actuators.Furthermore,with the application of 40 actuators,the method successfully reduces the rms surface error induced by gravitational deformation to below 12μm across all zenith angles.The proposed method is applied to typical deformation scenarios caused by environmental loads and panel misalignments,resulting in actuator adjustment schemes for varying numbers of actuators.A systematic evaluation of each scheme's impact on beam performances is provided,and further analysis reveals the relationship between actuator position distribution,adjustment values,and surface error.Additionally,the influence of surface error distributions on the selection of key actuators is systematically revealed. 展开更多
关键词 telescopes-instrumentation high angular resolution-methods numerical-methods analytical
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Research on the Error Budget of the Primary Mirror in JUST 认领 引用
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作者 Shi-Dong Shen Xiao-Fei Li +2 位作者 Hua Bai Yong Zhang De-Hua Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第4期74-81,共8页
The Shanghai Jiao Tong University Spectroscopic Telescope(JUST)holds significant importance for astronomy in China.It will assist scientists in achieving a series of influential research results in fields such as supe... The Shanghai Jiao Tong University Spectroscopic Telescope(JUST)holds significant importance for astronomy in China.It will assist scientists in achieving a series of influential research results in fields such as supernova explosions,identification of gravitational wave sources,and exoplanet detection with its outstanding sky survey capability and high-precision observation technology.The 4.4 m primary mirror of JUST will adopt segmented mirror active optics technology,which could be divided into two cases:the segmented primary mirror will be in co-focus under the limit of seeing;it will be equipped with adaptive optics,and the segmented primary mirror will achieve co-phasing in the near-infrared waveband(such as 1.8μm).This paper will focus on the research of errors in the hexagonal segments of the primary mirror under the two conditions.Additionally,separate and comprehensive error simulations were conducted,obtaining a large number of successful simulation results. 展开更多
关键词 telescopes-methods analytical-techniques high angular resolution
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OAM-radar imaging:A review 认领 引用
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作者 Rui Li Liulin Li +1 位作者 Hongping Zhou Zhongyi Guo 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第7期75-92,共18页
Due to the spiral phase wavefront of vortex electromagnetic waves(VEMW),there will exist the orbital angular momentum(OAM)in the VEMW,which supplies additional spatial dimensional for the information process.In radar ... Due to the spiral phase wavefront of vortex electromagnetic waves(VEMW),there will exist the orbital angular momentum(OAM)in the VEMW,which supplies additional spatial dimensional for the information process.In radar imaging,when the VEMW is used to illuminate targets,it can be regarded as the superposition of multiple plane waves incident on targets from various angles simultaneously.The target within the beam is radiated by electromagnetic(EM)fields with different phase information.These differences make the scattered echoes contain more target information.Providing a feasible technical path to improve the traditional radar imaging technology.This paper introduces the challenges faced by traditional radar imaging and the advantages of EM vortex wave imaging.It briefly derives the principles of vortex radar imaging and azimuthal resolution based on circular array antennas.Then,it reviews the development history and research status of vortex radar imaging technology,which divides into six research directions:vortex radar imaging model,Bessel function modulation,vortex radar gazing algorithm,EM vortex synthetic aperture radar(SAR)/inverse synthetic aperture radar(ISAR)imaging,vortex radar 3D imaging,and vortex radar forward imaging.Finally,the future development trends of vortex radar imaging technology are outlined and discussed. 展开更多
关键词 Vortex electromagnetic waves (VEMW) Orbital angular momentum (OAM) Vortex radar imaging Bessel function modulation
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Distorted dislocations and OAM spectra of twisted partially coherent noncanonical vortex-pair beams in non-Kolmogorov atmospheric turbulence 认领 引用
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作者 Chao Mei Ke Cheng +1 位作者 Hao Guo Xiao-Wen Yi 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第6期745-756,共12页
The twist phase has recently exhibited better resistance to turbulence-induced degeneration of the signal mode in orbital angular momentum(OAM)spectra.However,our attention is paid to exploring the combined influence ... The twist phase has recently exhibited better resistance to turbulence-induced degeneration of the signal mode in orbital angular momentum(OAM)spectra.However,our attention is paid to exploring the combined influence of the twist factor and noncanonical strength on“distorted dislocation”and OAM spectra in non-Kolmogorov atmospheric turbulence by introducing a noncanonical vortex-pair to twisted partially coherent beams.It is found that the twist factor or noncanonical strength can distort concentric ring dislocations in spatial correlation singularities into the so-called“distorted dislocations”.In turbulence propagation,noncanonical strengths can lead to annihilation and creation of distorted dislocations and change the number of dislocations,but twist factors cannot affect their number except for deepening the distortion in the structures.The explicit expression of the OAM flux density per photon,which was also derived,indicates that noncanonical strength can further improve the OAM capacity even if the twist factor reaches its extreme value.Compared to the twist factor,the noncanonical strength plays a more significant role in the signal modulation and detectivity of OAM spectra.If the combined effect of the twist factor and noncanonical strength is considered,the detection performance of the signal mode during long-distance turbulence propagation is distinctly better than that of only the twist factor or the noncanonical strength.The noncanonical strength should not be ignored due to its better performance in the OAM capacity and detection probability of the signal mode.This work may provide inspiration for OAM-based optical communication by the modulation of multi-degrees of freedom associated with noncanonical strengths and twist factors. 展开更多
关键词 orbital angular momentum noncanonical vortex-pair twist phase correlation singularity atmospheric turbulence
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Research on Multimodal RFI Cancellation in QTT-PAF Beamforming Based on the PCA Algorithm 认领 引用
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作者 Yi-Fan Qi Xin Pei +4 位作者 Peng Wu Ke Zhang Pei-Yuan Lian Yue-Fei Yan Cong-Si Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2026年第4期178-188,共11页
This study tackles the multimodal radio frequency interference(RFI) challenges encountered by the Qitai Radio Telescope by developing a comprehensive numerical model.The model integrates four critical interference typ... This study tackles the multimodal radio frequency interference(RFI) challenges encountered by the Qitai Radio Telescope by developing a comprehensive numerical model.The model integrates four critical interference types:coupling effects,fixed-position interference,moving-position interference,and white noise.These interferences exhibit dynamic variations in both temporal and spatial domains.Innovatively,this work introduces the principal component analysis(PCA) algorithm to beamforming for the first time,conducting a systematic performance comparison with the conventional sub space projection(SP) algorithm.The interference cancellation capability of PC A is rigorously evaluated under two scenarios:(ⅰ) complete spatial separation between signal of interest(SOI)and RFI,and(ⅱ) partial or full spatial overlap between SOI and RFI distributions.Results demonstrate that PC A achieves a 30 dB S/N improvement over SP while maintaining the same robust coupling effects as SP.Crucially,PCA better handles overlapping SOI-RFI scenarios,in which traditional methods exhibit significant performance degradation.This research provides a foundational framework for future beamformer design,offering significant potential to advance RFI mitigation technologies and enhance the observational robustness of radio telescopes in complex electromagnetic environments. 展开更多
关键词 Astronomical Instrumentation,Methods and Techniques-instrumentation high angular resolution-methods numerical-techniques radar astronomy
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Revealing Interfacial Orbital Transport in Nonmagnet/Ferromagnet Bilayers by the Absence of Orbital Hall Magnetoresistance 认领 引用
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作者 Yumin Yang Wenqi Xu +3 位作者 Zhicheng Xie Na Lei Jianhua Zhao Dahai Wei 《Chinese Physics Letters》 SCIE EI CAS CSCD 2026年第7期111-116,I0063-I0072,共6页
Orbital angular momentum transport has emerged as a promising route for spin-orbitronic devices,yet its transport behavior remains under debate and is often assumed to follow the phenomenology of spin transport.Here,w... Orbital angular momentum transport has emerged as a promising route for spin-orbitronic devices,yet its transport behavior remains under debate and is often assumed to follow the phenomenology of spin transport.Here,we reveal the distinct nature of interfacial orbital transport through the absence of orbital Hall magnetoresistance(OMR)in nonmagnet/ferromagnet bilayers,challenging the general assumption that orbital transport mimics spin transport.Despite the observation of giant orbital torques,which confirms the injection of orbital currents,thickness-dependent magnetoresistance measurements reveal that the magnetoresistance signal is dominated by the intrinsic magnetoresistance of the ferromagnet and current shunting,with no discernible OMR contribution.We attribute this contradiction to magnetization-independent orbital absorption within the ferromagnet,which allows the generation of orbital torque as one relaxation pathway but suppresses the interfacial reflection required for OMR.Additionally,we find that textureinduced magnetoresistance,self-torque,and interfacial effects in Ni-based bilayers may obscure genuine orbital signals,suggesting that caution is required when employing Ni in orbitronic studies.These findings clarify the distinct physical rules governing orbital transport and provide a simple method to distinguish between spin and orbital currents. 展开更多
关键词 orbital transport nonmagnet ferromagnet bilayers orbital angular momentum transport orbital Hall magnetoresistance interfacial orbital transport transport behavior giant orbital torqueswhich spin transportdespite
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