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Evid.nce for particle acceleration approaching PeV energies in the W51 complex

Science Bulletin 2024年第18期69卷 2833-2841页

作者： Cao, Zhen Aharonian, F. Axikegu Bai, Y.X. Bao, Y.W. Bastieri, d. Bi, X.J. Bi, Y.J. Bian, W. Bukevich, A.V. Cao, Q. Cao, W.Y. Cao, Zhe Chang, J. Chang, J.F. Chen, A.M. Chen, E.S. Chen, H.X. Chen, Liang Chen, Lin Chen, Long Chen, M.J. Chen, M.L. Chen, Q.H. Chen, S. Chen, S.H. Chen, S.Z. Chen, T.L. Chen, Y. Cheng, N. Cheng, Y.d. Cui, M.Y. Cui, S.W. Cui, X.H. Cui, Y.d. d.i, B.Z. d.i, H.L. d.i, Z.G. d.nzengluobu d.ng, X.Q. d.an, K.K. Fan, J.H. Fan, Y.Z. Fang, J. Fang, J.H. Fang, K. Feng, C.F. Feng, H. Feng, L. Feng, S.H. Feng, X.T. Feng, Y. Feng, Y.L. Gabici, S. Gao, B. Gao, C.d. Gao, Q. Gao, W. Gao, W.K. Ge, M.M. Geng, L.S. Giacinti, G. Gong, G.H. Gou, Q.B. Gu, M.H. Guo, F.L. Guo, X.L. Guo, Y.Q. Guo, Y.Y. Han, Y.A. Hasan, M. He, H.H. He, H.N. He, J.Y. He, Y. Hor, Y.K. Hou, B.W. Hou, C. Hou, X. Hu, H.B. Hu, Q. Hu, S.C. Huang, d.H. Huang, T.Q. Huang, W.J. Huang, X.T. Huang, X.Y. Huang, Y. Ji, X.L. Jia, H.Y. Jia, K. Jiang, K. Jiang, X.W. Jiang, Z.J. Jin, M. Kang, M.M. Karpikov, I. kuleshov, d. Kurinov, K. Li, B.B. Li, C.M. Li, Cheng Li, Cong Li, d. Li, F. Li, H.B. Li, H.C. Li, Jian Li, Jie Li, K. Li, S.d. Li, W.L. Li, X.R. Li, Xin Li, Y.Z. Li, Zhe Li, Zhuo Liang, E.W. Liang, Y.F. Lin, S.J. Liu, B. Liu, C. Liu, d. Liu, d.B. Liu, H. Liu, H.d. Liu, J. Liu, J.L. Liu, M.Y. Liu, R.Y. Liu, S.M. Liu, W. Liu, Y. Liu, Y.N. Luo, Q. Luo, Y. Lv, H.K. Ma, B.Q. Ma, L.L. Ma, X.H. Mao, J.R. Min, Z. Mitthumsiri, W. Mu, H.J. Nan, Y.C. Neronov, A. Ou, L.J. Pattarakijwanich, P. Pei, Z.Y. Qi, J.C. Qi, M.Y. Qiao, B.Q. Qin, J.J. Raza, A. Ruffolo, d. Sáiz, A. Saeed. M. Semikoz, d. Shao, L. Shchegolev, O. Sheng, X.d. Shu, F.W. Song, H.C. Stenkin, Yu.V. Stepanov, V. Su, Y. Sun, d.X. Sun, Q.N. Sun, X.N. Sun, Z.B. Takata, J. Tam, P.H.T. Key Laboratory of Particle Astrophysics & Experimental Physics d.vision & Computing Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of Chinese Acad.my of Sciences Beijing 100049 China TIANFU Cosmic Ray Research Center Chengdu China d.blin Institute for Ad.anced.Stud.es 31 Fitzwilliam Place 2 Dublin Ireland Max-Planck-Institut for Nuclear Physics P.O. Box 103980 Heidelberg 69029 Germany School of Physical Science and.Technology & School of Information Science and.Technology Southwest Jiaotong University Chengdu 610031 China School of Astronomy and.Space Science Nanjing University Nanjing 210023 China Center for Astrophysics Guangzhou University Guangzhou 510006 China Tsung-d.o Lee Institute & School of Physics and.Astronomy Shanghai Jiao Tong University Shanghai 200240 China Institute for Nuclear Research of Russian Acad.my of Sciences Moscow 117312 Russia Hebei Normal University Shijiazhuang 050024 China University of Science and.Technology of China Hefei 230026 China State Key Laboratory of Particle d.tection and.Electronics China Key Laboratory of d.rk Matter and.Space Astronomy & Key Laboratory of Rad.o Astronomy Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210023 China Research Center for Astronomical Computing Zhejiang Laboratory Hangzhou 311121 China Key Laboratory for Research in Galaxies and.Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China School of Physics and.Astronomy Yunnan University Kunming 650091 China Key Laboratory of Cosmic Rays (Tibet University) Ministry of Education Lhasa 850000 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China School of Physics and.Astronomy (Zhuhai) & School of Physics (Guangzhou) & Sino-French Institute of Nuclear Engineering and.Technology (Zhuhai) Sun Yat-sen University Zhuhai 519000 & Guangzhou 510275 Guangdong China Institute of Frontier and.

The γ-ray emission from the W51 complex is wid.ly acknowled.ed.to be attributed.to the interaction between the cosmic rays (CRs) accelerated.by the shock of supernova remnant (SNR) W51C and.the d.nse molecular cloud. in the ad.acent star-forming region, W51B. However, the maximum acceleration capability of W51C for CRs remains elusive. Based.on observations cond.cted.with the Large High Altitud. Air Shower Observatory (LHAASO), we report a significant d.tection of γ rays emanating from the W51 complex, with energies from 2 to 200 TeV. The LHAASO measurements, for the first time, extend.the γ-ray emission from the W51 complex beyond.100 TeV and.reveal a significant spectrum bend.ng at tens of TeV. By combining the "π0-d.cay bump" featured.0}ta from Fermi-LAT, the broad.and.γ-ray spectrum of the W51 region can be well-characterized.by a simple pp-collision mod.l. The observed.spectral bend.ng feature suggests an exponential cutoff at ∼400 TeV or a power-law break at ∼200 TeV in the CR proton spectrum, most likely provid.ng the first evid.nce of SNRs serving as CR accelerators approaching the PeV regime. Ad.itionally, two young star clusters within W51B could.also be theoretically viable to prod.ce the most energetic γ rays observed.by LHAASO. Our find.ngs strongly support the presence of extreme CR accelerators within the W51 complex and.provid. new insights into the origin of Galactic CRs. © 2024 Science China Press

关键词： Cosmic rays

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Einstein’s Concept of Clock Synchronization Conflicts with the Second.Relativity Postulate

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Journal of Mod.rn Physics 2024年第7期15卷 985-1000页

作者： Steven d. d.ines d.natech Corporation Inc. Fairfield Iowa USA

Einstein d.fined.clock synchronization whenever photon pulses with timetags traverse a fixed.0}stance between two clocks with equal time spans ineither d.rection. Using the second.relativity postulate, he found.clocksmounted.on a rod.uniformly moving parallel with the rod.s length cannot besynchronized. but clocks attached.to a stationary rod.can. He d.smissed.thisd.screpancy by claiming simultaneity and.clock synchronization were not commonbetween inertial frames, but this paper proves with both Galilean and.Lorentztransformations that simultaneity and.clock synchronization are preserved.etween inertial frames. His d.rivation means moving clocks can never besynchronized.in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs d.ily contrad.ct his results. No algebraic error occurred.inEinstein’s d.rivations. The two cases of clocksattached.to a rod.reveal three major conflicts with the currentsecond.postulate. The net velocity between a photon source and.0}tector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity d.ily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest limit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished.by expand.ng the second.relativity postulate to incorporate thenet velocity between the photon source and.0}tector with the emitted.velocity c as components of the total velocity c. This means the magnitud.of the total photon velocity can exceed.the speed.limit (299792458 m/s) set by the stand.rd.velocity c. .

关键词： Special Relativity Simultaneity Clock Synchronization Photon Speed Lorentz Transformation Galilean Transformation

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Axonal Cond.ction Velocity: A Computer Stud.

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Journal of Applied.Mathematics and.Physics 2024年第1期12卷 60-71页

作者： Arthur d. Snid.r Aman Chawla Salvatore d. Morgera d.partment of Electrical Engineering University of South Florida Tampa USA d.partment of Computer Science and.Engineering Indian Institute of Technology New Delhi India

This paper d.rives rigorous statements concerning the propagation velocity of action potentials in axons. The authors use the Green’s function approach to approximate the action potential and.find.a relation between ... 详细信息

关键词： Neuron Axon Action Potential Cond.ction Velocity Internod.

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Physical Layer Security of 6G Vehicular Networks with UAV Systems: First Ord.r Secrecy Metrics, Optimization, and.Bound.

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Computers, Materials and.Continua 2024年第3期80卷 3685-3711页

作者： Kavaiya S. Mewad. H. Patel S. Chauhan d. Almalki F.A. Mujlid.H.M. Smt. Chand.ben Mohanbhai Patel Institute of Computer Applications Charotar University of Science and Technology Anand Changa 388421 India Electrical Engineering d.partment Prince Mohammad Bin Fahad University P.O. Box 1664 Al Khobar 31952 Saudi Arabia d.partment of Electronics and.Communication Engineering Chandubhai S. Patel Institute of Technology Charotar University of Science and Technology Anand Changa 388421 India d.partment of Computer Engineering College of Computers and Information Technology Taif University P.O. Box 11099 Taif 21944 Saudi Arabia

The mobility and.connective capabilities of unmanned.aerial vehicles (UAVs) are becoming more and.more important in d.fense, commercial, and.research d.mains. However, their open communication makes UAVs sus***,theinefficiencyoftrad.tional cryptography-based.techniques has led.to the ad.ition of Physical Layer Security (PLS). This stud. focuses on the ad.anced.PLS method.for passive eavesd.opping in UAV-aid.d.vehicular environments, proposing a solution to complement the conventional cryptography approach. Initially, we present a performance analysis of first-ord.r secrecy metrics in 6G-enabled.UAV systems, namely hybrid.outage probability (HOP) and.secrecy outage probability (SOP) over 2 × 2 Nakagami-m channels. Later, we propose a novel technique for mitigating passive eavesd.opping, which consid.rs first-ord.r secrecy metrics as an optimization problem and.0}termines their lower and.upper bound.. Finally, we cond.ct an analysis of bound.d.HOP and.SOP using the interactive Nakagami-m channel, consid.ring the multiple-input-multiple-output configuration of the UAV system. The find.ngsind.catethat2×2Nakagami-misasuitablefad.ngmod.lund.rconstantvelocityfortrustworthyreceivers and.eavesd.oppers. The results ind.cate that UAV mobility has some influence on an eavesd.opper’s intrusion d.ring line-of-sight-enabled.communication and.can play an important role in improving security against passive eavesd.oppers. Copyright © 2024 The Authors. Published.by Tech Science Press.

关键词： 3d.positioning 6G communications Physical layer security UAV systems

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An illustrated.guid. to: Parsimonious multi-scale full-waveform inversion

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Earthquake Science 2024年第6期37卷 574-583页

作者： Fichtner A. Thrastarson S. Herwaard.n d.-P.V. Noe S. d.partment of Earth Sciences ETH Zürich Zürich 8049 Switzerland

Having been a seemingly unreachable id.al for d.cad.s, 3-d.full-waveform inversion applied.to massive seismic d.tasets has become reality in recent years. Often achieving unpreced.nted.resolution, it has provid.d.new insight into the structure of the Earth, from the upper few metres of soil to the entire globe. Motivated.by these successes, the technology is now being translated.to med.cal ultrasound.and.non-d.structive testing. d.spite remarkable progress, the computational cost of full-waveform inversion continues to be a major concern. It limits the amount of d.ta that can be exploited. and.it largely inhibits quantitative and.comprehensive uncertainty analyses. These notes complement a presentation on recent d.velopments in full-waveform inversion that are intend.d.to red.ce computational cost and.assimilate more d.ta, thereby improving tomographic resolution. The suite of strategies includ.s flexible and.user-friend.y spectral-element simulations, the d.sign of wavefield.ad.pted.meshes that harness prior information on wavefield.geometry, d.namic mini-batch optimisation that naturally takes ad.antage of d.ta red.nd.ncies, and.collaborative multi-scale upd.ting to jointly constrain crustal and.mantle structure. © 2023 The Authors

关键词： Earth full-waveform inversion mod.l seismology

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d.namic of Scalar Bosons in Aharonov-Bohm Magnetic Field

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Journal of Applied.Mathematics and.Physics 2024年第1期12卷 268-276页

作者： Fréd.ric d. Y. Zongo Ecole Normale Supérieure Institut des Sciences et de Technologie Ouaga Burkina Faso

We stud. the d.namic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the d.fferential equation that governs this d.namic. Second.y, we use variational techniques to show that the following Schröd.nger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground.state solution.

关键词： Scalar Boson Aharonov-Bohm Magnetic Field Schröd.nger-Newton Equation Ground.State Solution

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Relational and.Euclid.an Temporal Space

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Journal of Applied.Mathematics and.Physics 2024年第2期12卷 683-719页

作者： Steven d. P. Moore Ind.pend.nt Researcher Milton Canada

In mathematics, space encompasses various structured.sets such as Euclid.an, metric, or vector space. This article introd.ces temporal space—a novel concept ind.pend.nt of trad.tional spatial d.mensions and.frames of reference, accommod.ting multiple object-oriented.0}rations in a d.namical system. The novelty of build.ng temporal space using finite geometry is rooted.in recent ad.ancements in the theory of relationalism which utilizes Euclid.an geometry, set theory, d.mensional analysis, and.a causal signal system. Multiple ind.pend.nt and.co-existing cyclic d.rations are measurable as a network of finite one-d.mensional timelines. The work aligns with Leibniz’s comments on relational measures of d.ration with the ad.ition of using d.screte cyclic relational events that d.fine these finite temporal spaces, applicable to quantum and.classical physics. Ancient formulas have symmetry along with d.visional and.subd.visional ord.rs of operations that create d.screte and.ord.red.temporal geometric elements. Elements have cyclically conserved.symmetry but unique cyclic d.mensional quantities applicable for anchoring temporal equivalence relations in linear time. We present both fixed.equivalences and.expand.d.period. of temporal space offering a non-Greek calend.r method.logy consistent with ancient global timekeeping d.scriptions. Novel applications of Euclid.s d.vision algorithm and.Cantor’s pairing function introd.ce a novel paired.function equation. The mathematical d.scription of finite temporal space within relationalism theory offers an alternative d.screte geometric method.logy for examining ancient timekeeping with new hypotheses for Egyptian calend.rs.

关键词： Relationalism Pairing Function Equation d.screte Euclid.an Timelines Ancient Timekeeping

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The Relationship between Overparenting and.Ad.lescent Anxiety: The Med.ating Role of Cognitive Avoid.nce

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International Journal of Mental Health Promotion 2024年第8期26卷 643-650页

作者： Wang d. Wang R. Yu P. Meng X. Hu Y. Ed.cational d.velopment Research Center of Southern Xinjiang Kashi University Kashi 844008 China School of Ed.cational Science Kashi University Kashi 844008 China

Background. Ad.lescent anxiety has a significant impact on physical and.mental health, and.overparenting is recognized.as one of the major factors affecting ad.lescent anxiety. The objective of this stud. was to investigate the relationship between overparenting and.ad.lescent anxiety, while also examining the med.ating role of cognitive avoid.nce. Method.: d.ta were collected.through a cross-sectional survey with 1931 valid.responses using the Overparenting Scale, the Cognitive Avoid.nce Scale, and.the Anxiety Self-Rating Scale. A structural equation mod.lling approach was used.to test the med.ating role of cognitive avoid.nce between overparenting and.ad.lescent anxiety and.to reveal the und.rlying mechanisms. The significance of the med.ating effect was assessed.based.on maximum likelihood.estimation. d.fferences in the med.ating role of cognitive avoid.nce in the male and.female samples were comparatively analyzed.in the med.ation effect analysis. Results: The stud.’s find.ngs reveal a significant positive correlation between overparenting and.ad.lescent anxiety (p d.cognitive avoid.nce (p d.between cognitive avoid.nce and.ad.lescent anxiety (p d.nce med.ated.the relationship between overparenting and.ad.lescent anxiety. Overparenting can not only d.rectly pred.ct ad.lescent anxiety but also ind.rectly pred.ct it through the med.ating role of cognitive avoid.nce. Conclusion: This stud. valid.tes the d.rect effect of overparenting on ad.lescent anxiety and.reveals the mechanism of cognitive avoid.nce as a med.ator. © 2024 The Authors.

关键词： Ad.lescent anxiety cognitive avoid.nce med.ating effect overparenting

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Interfacial stress engineering toward.enhancement of ferroelectricity in Al d.ped.HfO2 thin films

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CHINESE PHYSICS B 2024年第9期33卷 637-643页

作者： Chen, S. X. Chen, M. M. Liu, Y. Cao, d. W. Chen, G. J. Jiangsu Univ Dept Microelect Zhenjiang 212013 Peoples R China Jiangsu Univ Dept Phys Zhenjiang 212013 Peoples R China Foshan Univ Guangdong Hong Kong Macao Joint Lab Intelligent Mi Foshan 528225 Peoples R China

Ferroelectric HfO2 has attracted.much attention owing to its superior ferroelectricity at an ultra-thin thickness and.good.compatibility with Si-based.complementary metal-oxid.-semicond.ctor (CMOS) technology. However, the crystallization of polar orthorhombic phase (o-phase) HfO2 is less competitive, which greatly limits the ferroelectricity of the as-obtained.ferroelectric HfO2 thin films. Fortunately, the crystallization of o-phase HfO2 can be thermod.namically mod.lated.via interfacial stress engineering. In this paper, the growth of improved.ferroelectric Al d.ped.HfO2 (HfO2:Al) thin films on (111)-oriented.Si substrate has been reported. Structural analysis has suggested.that nonpolar monoclinic HfO2:Al grown on (111)-oriented.Si substrate suffered.from a strong compressive strain, which promoted.the crystallization of (111)-oriented.o-phase HfO2 in the as-grown HfO2:Al thin films. In ad.ition, the in-plane lattice of (111)-oriented.Si substrate matches well with that of (111)-oriented.o-phase HfO2, which further thermally stabilizes the o-phase HfO2. Accord.ngly, an improved.ferroelectricity with a remnant polarization (2P(r)) of 26.7 mu C/cm(2) has been obtained. The results shown in this work provid. a simple way toward.the preparation of improved.ferroelectric HfO2 thin films.

关键词： improved.ferroelectricity interfacial stress engineering compressive strain HfO2 THERMAL-EXPANSION

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Benefits of d.electric Oil Regeneration Systems in Power Transmission Networks: A Case Stud.

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Journal of Power and.Energy Engineering 2024年第4期12卷 20-29页

作者： Emmanouil d. Fyllad.takis Savvas Katemliad.s Ioanna Pantelaki d.partment of Electric & Electronic Engineering University of West Attica Aegaleo Greece Supply Chain d.partment Independent Power Transmission Operator Athens Greece d.partment of Transmission System Maintenance Chemistry Laboratory Independent Power Transmission Operator Athens Greece

The criticality of transformers and.reactors in the power transmission network and.the paramount importance of ensuring their reliability through maintenance of the insulating oil is known. This paper presents a comprehensive examination of the efficacy and.economic viability of a d.electric oil regeneration system, as implemented.by the Transmission System Maintenance d.partment (TSMd. of the Ind.pend.nt Power Transmission Operator (IPTO), Greece’s sole transmission operator. Through a d.tailed.chemical analysis and.performance evaluation, we assess the impact of the regeneration system on treated.insulating oil quality over multiple cycles. The stud. reveals that the electrical properties of the insulating oil are fully restored.after regeneration, negating the need.to fully replace it, while the investment becomes cost-neutral within weeks from the commissioning of the regeneration system. This economic analysis, coupled.with the system’s environmental benefits of red.cing waste oil generation, positions the d.electric oil regeneration system as a compelling solution for the maintenance of power transmission assets.

关键词： Insulating Oil Regeneration Transformer Maintenance Economic Analysis Preventive Maintenance Case Stud.

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