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Simulation study on cosmic ray background at large zenith angle based on GRANDProto35 coincidence array experiment

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Nuclear Science and Techniques 2021年第1期32卷 35-45页

作者： xiang-li qian Xu Wang Hui-Ying Sun Zhen Wang Olivier Martineau-Huynh School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Sorbonne Paris Cite CNRS/IN2P3LPNHESorbonne UniversiteUniversite Paris DiderotParisFrance

Neutrino detection in the 100 PeV energy region is the ultimate means of studying the origin of ultra-highenergy cosmic rays,in which the large radio detection array giant radio array for neutrino detection(GRAND)project aims to use to decipher this century-old *** GRANDProto35 compact array is a microform of 35 radio prototype detectors for the GRAND experiment,which verifies the reliability of GRAND performance through operation,and data analysis of the prototype *** radio detectors are a novel development in recent years,and their indexes need to be verified by traditional detectors,the GRAND Cooperation Group designed and constructed the GRANDProto35 coincidence array composed of radio detectors and scintillation *** study simulated the changes in detection efficiency,effective area,and event rate of cosmic rays with zenith angle based on this coincidence *** study found that the 1017 eV energy region is sensitive to GRANDProto35 *** the energy exceeded 1017 eV,the array detection efficiency could reach more than 95%and the effective area was up to*29106 m2.A simulation study on cosmic ray events with large zenith angles showed that the event rate detected by the array decreased significantly with increasing zenith angle,and the event rate of cosmic rays was approximately 0.1 per day for a zenith angle of 75.This serves as the background pollution rate for neutrino observation caused by largeangle cosmic-ray events,providing an important reference for further *** study results will be verified after the joint operation of the coincidence array.

关键词： GRANDProto35 GEANT4 Scintillation detector Cosmic ray

Simulation study on performance optimization of a prototype scintillation detector for the GRANDProto35 experiment

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Nuclear Science and Techniques 2021年第5期32卷 71-83页

作者： xiang-li qian Hui-Ying Sun Cheng liu Xu Wang Olivier Martineau-Huynh School of Intelligent Engineering Shandong Management UniversityJinan 250357China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Sorbonne Universite Universite Paris DiderotSorbonne Paris CiteCNRS/IN2P3LPNHEParisFrance

As a proposed detector,the giant radio array for neutrino detection(GRAND)is primarily designed to discover and study the origin of ultra-high-energy cosmic rays,with ultra-high-energy neutrinos presenting the main method for detecting ultra-high-energy cosmic rays and their *** main principle is to detect radio emissions generated by ultra-high-energy neutrinos interacting with the atmosphere as they *** is the largest neutrino detection array to be built in ***35,as the first stage of the GRAND experiment,is a coincidence array composed of radio antennas and a scintillation detector,the latter of which,as a traditional detector,is used to perform cross-validation with radio detection,thus verifying the radio detection efficiency and enabling study of the background exclusion *** study focused on the implementation of the optimization simulation and experimental testing of the performance of the prototype scintillation detector used in GRANDProto35.A package based on GEANT4 was used to simulate the details of the scintillation detector,including the optical properties of its materials,the height of the light guide box,and position *** surface of the scintillator and the reflective materials used in the detector was optimized,and the influence of light guide heights and position inhomogeneity on the energy and time resolutions of the detector was *** to the simulation study,the number of scintillator photoelectrons increased when changing from the polished surface to the ground surface,with the appropriate design height for the light guide box being 50 cm and the appropriate design area for the scintillator being 0.5 m^(2).The performance of the detector was tested in detail through a coincidence experiment,and the test results showed that the number of photoelectrons collected in the detector was$84 with a time resolution of~1 ns,indicating good *** simulation results were consistent with

关键词： GRANDProto35 GEANT4 Scintillation detector light guide height Photoelectrons

Thinking process rules extraction for manufacturing process design

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Advances in Manufacturing 2017年第4期5卷 321-334页

作者： Jing-Tao Zhou xiang-qian li Ming-Wei Wang Rui Niu Qing Xu Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of Education of ChinaNorthwestern Polytechnical University Xi'an 710072People's Republic of China Department of Software and Information Service Research Electronic Technology Information Research Institute Ministry of Industry and Information Technology of the People's Republic of China Beijing 100040 People's Republic of China

To realize the reuse of process design knowledge and improve the efficiency and quality of process design, a method for extracting thinking process rules for process design is proposed. An instance representation model of the process planning reflecting the thinking process of techni- cians is established to achieve an effective representation of the process documents. The related process attributes are extracted from the model to form the related events. The manifold learning algorithm and clustering analysis are used to preprocess the process instance data. A rule extraction mechanism of process design is introduced, which is based on the related events after dimension reduction and clustering, and uses the association rule mining algorithm to realize the similar process information extraction in the same cluster. Through the vectorization description of the related events, the final process design rules are formed. Finally, an example is given to evaluate the method of process design rules extraction.

关键词： Process design rules Process design rules extraction Process planning model Related event Manifold learning

A novel trigger algorithm for wide-field-of-view imaging atmospheric Cherenkov technique experiments

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Nuclear Science and Techniques 2022年第3期33卷 22-28页

作者： Guang-Guang Xin Hao Cai Yi-Qing Guo Tian-Lu Chen Cheng liu xiang-li qian School of Physics and Technology Wuhan UniversityWuhan 430072China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China School of Intelligent Engineering Shandong Management UniversityJinan 250357China

The high-altitude detection of astronomical radiation(HADAR)experiment is a new Cherenkov observation technique with a wide field of view(FoV),aimed at observing the prompt emissions ofγ-ray bursts(GRBs).The bottleneck for this type of experiment can be found in determining how to reject the high rate of nightsky background(NSB)noise from random *** this work,we propose a novel method for rejecting noise,which considers the spatial properties of GRBs and the temporal characteristics of Cherenkov *** space coordinates,the map between the celestial sphere and the fired photomultiplier tubes(PMTs)on the telescope's camera can be expressed as f(δ(i,j))=δ'(i',j'),which means that a limited number of PMTs is selected from one *** the temporal scale,a 20-ns time window was selected based on the knowledge of Cherenkov *** allowed integration of the NSB for a short time ***,the angular resolution and effective area at 100 GeV in the HADAR experiment were obtained as 0.2°and 10^(4)m^(2),*** method can be applied to all wide-FoV experiments.

关键词： IACTs Wide field of view(FoV) γ-ray burst Cherenkov radiation

An Injectable Hydrogel with or without Drugs for Prevention of Epidural Scar Adhesion after Laminectomy in Rats

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Chinese Journal of Polymer Science 2016年第2期34卷 147-163页

作者： lin Chen xiang-qian li Lu-ping Cao Xi-lei li Jun-rong Meng 董健俞麟 Jian-dong Ding State Key Laboratory of Molecular Engineering of Polymers&Department of Macromolecular Science Fudan UniversityShanghai 200433China Department of Orthopaedic Surgery Zhongshan HospitalFudan UniversityShanghai 200032China

Epidural scarring occurs inevitably in the defect after spinal laminectomy, and thus how to prevent or reduce it becomes a challenging topic. In the present study, an injectable hydrogel and its dexamethasone （DEX）-loaded hydrogel systems were adopted to prevent epidural scarring in a postlaminectomy rat model. The hydrogel system composed of poly（D,L-lactic acid-co-glycolic acid）-poly（ethylene glycol）-poly（D,L-lactic acid-co-glycolic acid）（PLGA-PEG-PLGA） triblock copolymers was a free-flowing sol at room temperature, and spontaneously turned into a semi-solid gel at body temperature. A lumbar 3 total laminectomy was performed on Sprague Dawley （SD） rats, and the efficacy of the injectable hydrogel with or without drugs in preventing epidural scar formation was evaluated via the gross anatomical observation and histological examination at one month post-surgery. The results demonstrate that the use of hydrogel alone reduced epidural scarring significantly, whereas the efficacy of the DEX-loaded hydrogels presented an irregular dose-dependency of drug and even the inappropriate drug doses resulted in the negative results. Therefore, the present study confirms that the PLGA-PEG- PLGA hydrogel holds potential as a barrier device to decrease peridural scarring, and reveals that the sustained delivery of the steroid hormone DEX to prevent surgery-related adhesions in the laminectomy defect is complex. Moreover, our in vivo studies also remind the researchers to pay attention to the irregular dose-dependency of the hormone drugs.

关键词： Thermo-reversible hydrogel Epidural scarring Laminectomy Steroid hormone.

First-principles investigation of the valley and electrical properties of carbon-dopedα-graphyne-like BN sheet

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Chinese Physics B 2021年第5期30卷 568-575页

作者： Bo Chen xiang-qian li lin Xue Yan Han Zhi Yang Long-Long Zhang College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China

Based on ab initio density functional theory calculations,we demonstrate that two carbon-doped boron nitride analog ofα-graphyne structures,B_(3) C_(2) N_(3)) and BC_(6) N monolayers,are two-dimensional direct wide band gap semiconductors,and there are two inequivalent valleys in the vicinities of the vertices of their hexagonal Brillouin ***,B_(3)C_(2)N_(3) and BC_(6)N monolayers exhibit relatively high carrier mobilities,and their direct band gap feature is robust against the biaxial *** importantly,the energetically most favorable B_(3)C_(2)N_(3) and BC_(6)N bilayers also have direct wide band gaps,and valley polarization could be achieved by optical ***,we show that BC_(6) N monolayer might have high efficiency in photo-splitting reactions of water,and a vertical van der Waals heterostructure with a type-Ⅱenergy band alignment could be designed using B_(3)C_(2)N_(3)and BC_(6)N *** the above-mentioned characteristics make B_(3)C_(2)N_(3) and BC_(6)N monolayers,bilayers,and their heterostructures recommendable candidates for applications in valleytronic devices,metal-free photocatalysts,and photovoltaic cells.

关键词： first-principles calculations α-graphyne like structures valleytronic materials wide band gap semiconductors

A strange star scenario for the formation of eccentric millisecond pulsar PSR J1946+3417

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Research in Astronomy and Astrophysics 2021年第9期21卷 185-192页

作者： Long Jiang Na Wang Wen-Cong Chen Wei-Min liu Chun-Wei Leng Jian-Ping Yuan xiang-li qian Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Science Qingdao University of TechnologyQingdao 266525China School of Physics and Electrical Information Shangqiu Normal UniversityShangqiu 476000China Department of Intelligent Engineering Shandong Management UniversityJinan 250357China

PSR J1946+3417 is a millisecond pulsar(MSP)with a spin period P?3.17 *** in a binary with an orbital period Pb?27 days,the MSP is accompanied by a white dwarf(WD).The masses of the MSP and the WD were determined to be 1.83 M⊙,and 0.266 M⊙,***,its orbital eccentricity is e?0.134,which is challenging the recycling model of *** that the neutron star in a binary may collapse to a strange star when its mass reaches a critical limit,we propose a phase transition(PT)scenario to account for the origin of the *** sudden mass loss and the kick induced by asymmetric collapse during the PT may result in the orbital *** the PT event takes place after the mass transfer ceases,the eccentric orbit cannot be re-circularized in the Hubble *** at the masses of both components,we simulate the evolution of the progenitor of PSR J1946+3417 via *** simulations show that an NS/main sequence star binary with initial masses of 1.4+1.6 M⊙in an initial orbit of 2.59 days will evolve into a binary consisting of a 2.0 M⊙MSP and a 0.27 M⊙WD in an orbit of~21.5 *** that the gravitational mass loss fraction during PT is 10%,we simulate the effect of PT via the kick program of BSE with a velocity ofσPT=60 km *** results show that the PT scenario can reproduce the observed orbital period and eccentricity with higher probability than other values.

关键词： stars:neutron stars:evolution pulsars:individual(J1946+3417)

On the Formation of the Double Neutron Star Binary PSR J1846-0513

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Research in Astronomy and Astrophysics 2024年第11期24卷 259-267页

作者： Long Jiang Kun Xu Shuai Zha Yun-Lang Guo Jian-Ping Yuan xiang-li qian Wen-Cong Chen Na Wang School of Science Qingdao University of TechnologyQingdao 266525China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Physics and Electrical Information Shangqiu Normal UniversityShangqiu 476000China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Astronomy Nanjing UniversityNanjing 210023China Department of Intelligent Engineering Shandong Management UniversityJinan 250357China

The double neutron star PSR J1846-0513 is discovered by the Five-hundred-meter Aperture Spherical radio Telescope(FAST)in Commensal Radio Astronomy FAST *** pulsar is revealed to be harbored in an eccentric orbit with e=0.208 and an orbital period of 0.613 *** total mass of the system is constrained to b2.6287(35)M_(⊙),with a mass upper limit of 1.3455 M_(⊙)for the pulsar and a mass lower limit of 1.2845 M_(⊙)for th companion *** reproduce its evolution history,we perform a 1D model for the formation of PSR J1846-0513whose progenitor is assumed to be neutron star—helium(He)star system via MESA *** the larg eccentricity is widely believed to originate from an asymmetric supernova explosion,we also investigate th dynamical effects of the supernova *** simulated results show that the progenitor of PSR J1846-0513could be a binary system consisting of a He star of 3.3-4.0 M_(⊙)and a neutron star in a circular orbit with an initia period of~0.5 day.

关键词： stars evolution stars neutron (stars:)binaries general stars individual(PSR J1864-0513)

Gamma/Hadron Separation Method for the HADAR Experiment

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Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren Tian-Lu Chen You-liang Feng Dan-Zeng Luo-Bu Yi-Qing Guo Cheng liu Qi Gao Mao-Yuan liu xiang-li qian Ya-Ping Wang Zi-Hao Zhang Xin-Long li Qing-Yuan Hou Heng-Jiao liu Qing-qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis