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Research in Astronomy and Astrophysics 2024年第8期24卷 42-51页

作者： Jin-Hui Rao Shu-Xu Yi Lian Tao Qing-Wen Tang Department of physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China institute of high energy {3. Chinese Academy of SciencesBeijing 100049China

Theories of modified gravity suggest that the propagation speed of gravitational waves(GW)v_gmay deviate from the speed of light c.A constraint can be placed on the difference between c and v_gwith a simple method that uses the arrival time delay between GW and electromagnetic wave simultaneously emitted from a burst *** simulated the joint observation of GW and short gamma-ray burst signals from binary neutron star merger events in different observation campaigns,involving advanced LIGO(aLIGO)in design sensitivity and Einstein Telescope(ET)joint-detected with Fermi/*** a result,the relative precision of constraint on v_gcan reach~10~(-17)(aLIGO)and~10^(-18)(ET),which are one and two orders of magnitude better than that from GW170817,*** continue to obtain the bound of graviton mass m_g≤7.1(3.2)×10~(-20)eV with aLIGO(ET).Applying the Standard-Model Extension test framework,the constraint on v_gallows us to study the Lorentz violation in the nondispersive,nonbirefringent limit of the gravitational *** obtain the constraints of the dimensionless isotropic coefficients S_(00)^(4)at mass dimension d=4,which are-1×10^(-15)

关键词： gravitational waves-(stars)gamma-ray burst general-stars neutron

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu Fu-San Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China institute of high energy {3. Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Refined symmetry-resolved Page curve and charged black holes

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Chinese physics C 2024年第5期48卷 134-140页

作者：李磐凌意 institute of high energy {3. Chinese Academy of SciencesBeijing 100049China School of physics University of Chinese Academy of SciencesBeijing 100049China

The Page curve plotted using the typical random state approximation is not applicable to a system with conserved quantities,such as the evaporation process of a charged black hole,during which the electric charge does not macroscopically radiate out with a uniform *** this context,the symmetry-resolved entanglement entropy may play a significant role in describing the entanglement structure of such a *** attempt to impose constraints on microscopic quantum states to match the macroscopic phenomenon of charge radiation during black hole ***,we consider a simple qubit system with conserved spin/charge serving as a toy model for the evaporation of charged black *** propose refined rules for selecting a random state with conserved quantities to simulate the distribution of charges during the different stages of evaporation and obtain refined Page curves that exhibit distinct features in contrast to the original Page *** find that the refined Page curve may have a different Page time and exhibit asymmetric behavior on both sides of the Page *** refined Page curves may provide a more realistic description for the entanglement between the charged black hole and radiation during the evaporation process.

关键词： quantum entanglement Page curve charged black hole black hole evaporation Hawking radiation Schwinger effect random state average entropy

The energy response of LaBr_(3.(Ce),LaBr_(3.(Ce,Sr),and NaI(Tl)crystals for GECAM

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Nuclear Science and Techniques 2024年第2期35卷 110-122页

作者： Pei-Yi Feng Xi-Lei Sun Zheng-Hua An Yong Deng Cheng-Er Wang Huang Jiang Jun-Jie Li Da-Li Zhang Xin-Qiao Li Shao-Lin Xiong Chao Zheng Ke Gong Sheng Yang Xiao-Jing Liu Min Gao Xiang-Yang Wen Ya-Qing liu Yan-Bing Xu Xiao-Yun Zhao Jia-Cong Liu Fan Zhang Hong Lu Particle and Astrophysics Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Experimental physics Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.and General Research Institute for Nonferrous MetalsBeijing 100088China

The GECAM series of satellites utilizes LaBr_(3.(Ce),LaBr_(3.(Ce,Sr),and NaI(Tl)crystals as sensitive materials for gamma-ray detectors(GRDs).To investigate the nonlinearity in the detection of low-energy gamma rays and address the errors in the calibration of the E-C relationship,comprehensive tests and comparative studies of the three aforementioned crystals were conducted using Compton electrons,radioactive sources,and mono-energetic *** nonlinearity test results of the Compton electrons and X-rays demonstrated substantial differences,with all three crystals presenting a higher nonlinearity for X/-rays than for Compton *** the LaBr_(3.(Ce)and LaBr_(3.(Ce,Sr)crystals having higher absolute light yields,they exhibited a noticeable nonlinear decrease in the light yield,especially at energies below 400 *** NaI(Tl)crystal demonstrated an"excess"light output in the 6-200 keV range,reaching a maximum"excess"of 9.2%at 3. keV in the X-ray testing and up to 15.5%at 14 keV during Compton electron testing,indicating a significant advantage in the detection of low-energy gamma ***,we explored the underlying causes of the observed nonlinearity in these *** study not only elucidates the detector responses of GECAM,but also initiates a comprehensive investigation of the nonlinearity of domestically produced lanthanum bromide and sodium iodide crystals.

关键词： LaBr_(3.(Ce)detector LaBr_(3.(Ce,Sr)detector NaI(Tl)detector GECAM energy response Light yield nonlinearity

Detector performance of the Gamma-ray Transient Monitor onboard DRO-A satellite

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Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 75-90页

作者： Pei-Yi Feng Zheng-Hua An Da-Li Zhang Chen-Wei Wang Chao Zheng Sheng Yang Shao-Lin Xiong Jia-Cong Liu Xin-Qiao Li Ke Gong Xiao-Jing Liu Min Gao Xiang-Yang Wen Ya-Qing Liu Xiao-Yun Zhao Fan Zhang Xi-Lei Sun Hong Lu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.

关键词： NaI(Tl)detector energy response ground calibration gamma-ray detector DRO-A satellite

Simulation and reconstruction of particle trajectories in the CEPC drift chamber

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Nuclear Science and Techniques 2024年第8期35卷 9-22页

作者： Meng‑Yao Liu Wei‑Dong Li Xing‑Tao Huang Yao Zhang Tao Lin Ye Yuan institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China institute of high energy {3. Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The circular electron-positron collider(CEPC)is designed to precisely measure the properties of the Higgs boson,study electroweak interactions at the Z-boson peak,and search for new physics beyond the Standard *** a component of the 4th conceptual CEPC detector,the drift chamber facilitates the measurement of charged *** study implemented a Geant4-based simulation and track reconstruction for the drift *** the simulation,detector construction and response were implemented and added to the CEPC simulation *** development of track reconstruction involves track finding using the combinatorial Kalman filter method and track fitting using the tool of *** the simulated data,the tracking performance was *** results showed that both the reconstruction resolution and tracking efficiency satisfied the requirements of the CEPC experiment.

关键词： CEPC Drift chamber Detector simulation Track reconstruction

A muon high-resolution pseudorange measurement method: Application to muon navigation in confined spaces

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Chinese Journal of Aeronautics 2024年第4期37卷 391-404页

作者： Haoyang LI Chunxi ZHANG Xingming FAN Longjie TIAN Tianqi LI Yang PANG Yanqiang YANG institute of Optics and Electronics School of Instrumentation Science and Optoelectronics EngineeringBeihang UniversityBeijing 100191China institute of high energy {3. Chinese Academy of SciencesBeijing 100049China

Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces *** this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight ***, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.

关键词： Muon navigation Cosmic ray muons Muon detection technology Muon transmission technology Pseudorange measurement

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-Sheng Xu Chun-Tao Lin Na Wang Jing-Ye Xu Yuan Zhang Key Laboratory of Particle Acceleration physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

Theoretical design of polyazole based ligands for the separation of Am(Ⅲ)/Eu(Ⅲ)

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Chinese Chemical Letters 2024年第8期35卷 406-412页

作者： Lingling Su Qunyan Wu Congzhi Wang Jianhui Lan Weiqun Shi School of Nuclear Science and Technology University of South ChinaHengyang 421001China Laboratory of Nuclear energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The extraction of radioactive minor actinides(An(Ⅲ))from lanthanides(Ln(Ⅲ))is an extremely impor-tant step in nuclear waste *** ligands with high-performance actinide-selectivity re-mains an essential *** works have reported that some polyazole based ligands exhibit good An(Ⅲ)/Ln(Ⅲ)separation ***,we first evaluated the effects of different polyazole side chains on the Am(Ⅲ)/Eu(Ⅲ)selectivity by exploring three pyridine-derived polyazole ligands L^(1),L^(2)and L^(3.with 1,2,4-triazole,1,2,3.triazole,and pyrazole side chains,respectively,using scalar relativistic theoretical *** coordination structures,bonding properties and thermodynamic behaviors of AmL(NO_(3.)_(3.and EuL(NO_(3.)_(3.complexes were investigated,which clarifies that the side chains do affect the electronic structure of ligand and its selectivity for Am(Ⅲ)/Eu(Ⅲ)***,L^(1)with 1,2,4-triazole side chains exhibited the highest selectivity for Am(Ⅲ)over Eu(Ⅲ)while the lowest complexation ability for metal ions among the three pyridine-derived polyazole ***,we designed a new ligand L^(4)con-taining 1,2,4-triazole side chains and a preorganized phenanthroline ***,such a new ligand was verified to show stronger complexation ability and higher selectivity for Am(Ⅲ)/Eu(Ⅲ)ions than L^(1).This work clarifies the complexation nature of polyazole based ligands with Am(Ⅲ)/Eu(Ⅲ)ions and provides design strategies for highly efficient polyazole based ligands for An(Ⅲ)/Ln(Ⅲ)separation.

关键词： Solvent extraction Am(Ⅲ)/Eu(Ⅲ)separation Polyazole based ligands Design strategy Density functional theory

Prospects to study hyperon-nucleon interactions at BESIII

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Chinese physics C 2024年第7期48卷 22-30页

作者：代建平李海波妙晗张剑宇 Department of physics Yunnan UniversityKunming 650091China institute of high energy {3. Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The prospects to study hyperon-nucleus/nucleon interactions at BESIII and similar e^(+)e^(-)colliders are analyzed in this *** the large quantity of hyperons produced by the decay of 10 billion J/■and 2.7 billion(3.86)collected at BESIII,the cross sections of several specific elastic and inelastic hyperon-nucleus reactions can be measured via scattering between hyperons and nucleus in the dense objects of the BESIII ***,the cross sections of the corresponding hyperon-nucleon interactions can be extracted from further phenomenological *** interactions between antihyperons and nucleus/nucleon,including scattering and annihilation,can also be studied using the method proposed in this *** results will definitely benefit the realization of precise probes for hyperon-nuclei/nucleus interactions and establish constraints to study the potential of strong interaction,the origin of color confinement,a unified model for baryon-baryon interactions,and the internal structure of neutron *** addition,the desirable prospects of corresponding studies in the future Super Tau-Charm Factory(STCF)are discussed and estimated in this study.

关键词： hyperon-nucleon interaction BESIII STCF neutron star