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Deep view of composite SNR cTA1 with LhAASO in γ-rays up to 300 TeV

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Science china(Physics,mechanics & Astronomy) 2025年

作者： Zhen cao f.Aharonian Axikegu y.X.bai y.W.bao D.bastieri X.j.bi y.j.bi W.bian A.V.bukevich Q.cao W.y.cao Zhe cao j.chang j.f.chang 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.chen N.cheng y.D.cheng m.c.chu m.y.cui S.W.cui X.h.cui y.D.cui b.Z.Dai h.L.Dai Z.G.Dai Danzengluobu X.Q.Dong K.K.Duan j.h.fan y.Z.fan j.fang j.h.fang K.fang c.f.feng h.feng L.feng S.h.feng X.T.feng y.f.ng y.L.feng S.Gabici b.Gao c.D.Gao Q.Gao W.Gao W.K.Gao m.m.Ge T.T.Ge L.S.Geng G.Giacinti G.h.Gong Q.b.Gou m.h.Gu f.L.Guo j.Guo X.L.Guo y.Q.Guo y.y.Guo y.A.han O.A.hannuksela m.hasan h.h.he h.N.he j.y.he y.he y.K.hor b.W.hou c.hou X.hou h.b.hu Q.hu S.c.hu c.huang D.h.huang T.Q.huang W.j.huang X.T.huang X.y.huang y.huang y.y.huang X.L.ji h.y.jia K.jia h.b.jiang K.jiang X.W.jiang Z.j.jiang m.jin m.m.Kang I.Karpikov D.Khangulyan D.Kuleshov K.Kurinov 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 W.L.Li X.R.Li Xin Li y.Z.Li Zhe Li Zhuo Li E.W.Liang y.f.Liang S.j.Lin 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.Liu Q.Luo y.Luo h.K.Lv b.Q.ma L.L.ma X.h.ma j.R.mao Z.min W.mitthumsiri h.j.m. y.c.Nan A.Neronov K.c.y.Ng L.j.Ou P.Pattarakijwanich Z.y.Pei j.c.Qi m.y.Qi b.Q.Qiao j.j.Qin A.Raza D.Ruffolo A.Sáiz m.Saeed D.Semikoz L.Shao O.Shchegolev X.D.Sheng f.W.Shu h.c.Song yu.V.Stenkin V.Stepanov y.Su D.X.Sun Q.N.Sun X.N.Sun Z.b.Sun j.Takata P.h.T.Tam Q.W.Tang R.Tang Z.b.Tang W.W.Tian L.h.Wan c.wang c.b.wang G.W.wang h.G.wang h.h.wang j.c.wang Kai wang Kai wang L.P.wang L.y.wang P.h.wang R.wang W.wang X.G.wang X.y.wang y.wang y.D.wang y.j.wang Z.h.wang Z.X.wang Zhen wang Zheng wang D.m.Wei j.j.Wei y.j.Wei T.Wen c.y.Wu h.R.Wu Q.W.Wu S.Wu X.f.Wu y.S.Wu S.Q.Xi j.Xia G.m.Xiang D.X.Xiao G.Xiao y.L.Xin y.Xing D.R.Xiong Z.Xiong D.L.xu R.f.xu R.X.xu W.L.xu L.xue D.h.yan j.Z.yan T.yan c.W.yang c.y.yang f.yang f.f.yang L.L.yang m.j.yang R.Z.yang W.X.yang y.h.yao Z.G.yao L.Q.yin N.yin X.h.you Z.y.you y.h Southwest jiaotong University School of Astronomy and Space Science Nanjing University center for Astrophysics Guangzhou University Tsung-Dao Lee Institute & School of Physics and Astronomy Shanghai jiao Tong University Institute for Nuclear Research of Russian Academy of Sciences h.b.i Normal University University of Science and Technology of china LhAASO collaboration State Key Laboratory of Particle Detection and Electronics Key Laboratory of Dark matter and Space Astronomy & Key Laboratory of Radio Astronomy Purple mountain Observatory chinese Academy of Sciences Research center for Astronomical computing Zhejiang Laboratory Key Laboratory.f.r Research in Galaxies and cosmology Shanghai Astronomical Observatory chinese Academy of Sciences School of Physics and Astronomy Key Laboratory of Particle Astrophysics & Experimental Physics Division & computing center yunnan University Key Laboratory of cosmic Rays (Tibet University) ministry of Education Department of Physics The chinese University of hong Kong Key Laboratory of Radio Astronomy and Technology National Astronomical Observatories chinese Academy of Sciences School of Physics and Astronomy (Zhuhai) & School of Physics (Guangzhou) & Sino-french Institute of Nuclear Engineering and Technology (Zhuhai) Sun yat-sen University Institute of high Energy Physics Institute of frontier and Interdisciplinary Science Shandong University APc Université Paris cité cNRS/IN2P3 cEA/IRfU Observatoire de Paris Department of Engineering Physics & Department of Astronomy Tsinghua University School of Physics and microelectronics chinese Academy of Sciences Zhengzhou University yunnan Observatories chinese Academy of Sciences china center of Advanced Science and Technology college of Physics Sichuan University School of Physics Peking University Guangxi Key Laboratory.f.r Relativistic Astrophysics School of Physical Science and Technology University of chinese Academy of Sciences Guangxi University Department of Physics faculty of Science mahidol University moscow Institute

The ultra-high-energy（UhE） gamma-ray source 1LhAASO j0007+7303u is positionally associated with the composite SNR cTA1 that is located at high Galactic Latitude b ≈ 10.5°. This provides a rare opportunity to spatially resolve the component of the pulsar wind nebula（PWN） and supernova remnant（SNR） at UhE. This paper conducted a dedicated data analysis of 1LhAASO j0007+7303u using the data collected from December 2019 to july 2023. This source is well detected with significances of 21σ and 17σ at 8-100 TeV and >100 TeV, respectively. The corresponding extensions are determined to be 0.23°±0.03°and 0.17°±0.03°. The emission is proposed to originate from the relativistic electrons accelerated within the PWN of PSR j0007+7303. The energy spectrum is well described by a power-law with an exponential cutoff function dN/dE =（42.4 ± 4.1）(E/（20 TeV）)-2.31±0.11exp(-E/（110±25 TeV）) TeV-1cm-2s-1in the energy range from 8 to 300 TeV, implying a steady-state parent electron spectrum dNe/dEe∝(Ee/（100 TeV）)-3.13±0.16exp[(-Ee/（373±70 TeV）)2] at energies above ≈ 50 TeV. The cutoff energy of the electron spectrum is roughly equal to the expected current maximum energy of particles accelerated at the PWN terminal shock. combining the X-ray and gamma-ray emission, the current space-averaged magnetic field can be limited to≈ 4.5 μG. To satisfy the multi-wavelength spectrum and the γ-ray extensions, the transport of relativistic particles within the PWN is likely dominated by the advection process under the free-expansion phase assumption.

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LhAASO detection of very-high-energy γ-ray emission surrounding PSR j0248+6021

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Science china(Physics,mechanics & Astronomy) 2025年

We report the detection of an extended very-high-energy(VhE) γ-ray source coincident with the location of middle-aged(62.4 kyr) pulsar PSR j0248+6021, by using the LhAASO-WcDA data of live 796 d and LhAASO-Km2A data of live 1216d. A significant excess of γ-ray induced showers is observed both.b. WcDA in energy bands of 1-25 Te V and Km2A in energy bands of >25 TeV with 7.3σ and 13.5σ, respectively. The best-fit position derived through WcDA data is R.A. = 42.06°± 0.12°and Dec. = 60.24°± 0.13°with an extension of 0.69°±0.15°and that of the Km2A data is R.A.= 42.29°± 0.13°and Dec. =60.38°± 0.07°with an extension of 0.37°±0.07°. No clear extended multiwavelength counterpart of this LhAASO source has been found from the radio band to the GeV band. The most plausible explanation of the VhE γ-ray emission is the inverse compton process of highly relativistic electrons and positrons injected by the pulsar. These electrons/positrons are hypothesized to be either confined within the pulsar wind nebula or to have already escaped into the interstellar medium, forming a pulsar halo.

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Observation of the γ-ray emission from W43 with LhAASO

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Science china(Physics,mechanics & Astronomy) 2025年

In this paper, we report the detection of the very-high-energy (VhE, 100 Ge V100 TeV) γ-ray emissions from the direction of the young star-forming region W43, observed by the Large high Altitude Air Shower Observation (LhAASO). The extended γ-ray source was detected with a significance of～16σby Km2A and～17σby WcDA, respectively. The angular extension of this γ-ray source is about 0.5 degrees, corresponding to a physical size of about 50pc. We discuss the origin of the γ-ray emission and possible cosmic ray acceleration in the W43 region using multi-wavelength data. Our findings suggest that W43 is likely another young star cluster capable of accelerating cosmic rays (cRs) to at least several hundred TeV.

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Relationship between the fatigue behavior and grain structures of an as-extruded mg-6.2%Zn-0.6%Zr(in wt.%)alloy

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journal of materials Science & Technology 2023年第18期149卷 119-126页

作者： b.j.wang D.K.xu c.L.jiang L.y.Sheng E.h.han School of Environmental and chemical Engineering Shenyang Ligong UniversityShenyang 110159China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China binzhou Institute of Technology Binzhou 256606China Shandong Key Laboratory of Advanced Aluminium materials and Technology Binzhou 256606China Shenzhen Institute Shenzhen Key Lab Human Tissue Regenerate&RepairPeking UniversityShenzhen 518057China

Through investigating the tension-tension fatigue behavior of an as-extruded mg-6.2 wt.%Zn-0.6 wt.%Zr(ZK60)alloy,it revealed that the determined fatigue strength at 107 cycles was quite sensitive to the grain *** them,the fine grain structure had the highest fatigue strength of 130 mPa,whereas the typical“bi-modal”grain structure had the lowest fatigue strength of 110 *** analysis demon-strated that for the fine grain structure,fatigue cracks preferentially nucleated at grain *** the“bi-modal”and coarse grain structures,the fatigue crack initiation was dominated by the cracking along slip bands.

关键词： mg alloys Grain structure cyclic slips fatigue behavior crack initiation

fAST Observations of an Extremely Active Episode of fRb 20201124A:Ⅰ.burst morphology

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Research in Astronomy and Astrophysics 2022年第12期22卷 54-69页

作者： D.j.Zhou j.L.han b.Zhang K.j.Lee W.W.Zhu D.Li W.c.jing W.-y.wang y.K.Zhang j.c.jiang j.R Niu R Luo h.xu c.f.Zhang b.j.wang j.W.xu P.wang Z.L.yang y.f.ng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy University of Chinese Academy of SciencesBeijing 100049China cAS Key Laboratory of fAST NAOCChinese Academy of SciencesBeijing 100101China Department of Physics and Astronomy University of NevadaLas VegasNV 89154USA Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Peking UniversityBeijing 100871China cSIRO Space and Astronomy EppingNSW 1710Australia Research center for Intelligent computing Platforms Zhejiang LaboratoryHangzhou 311100China

We report the properties of more than 600 bursts(including cluster-bursts)detected from the repeating fast radio burst(fRb)source fRb 20201124A with the five-hundred-meter Aperture Spherical radio Telescope during an extremely active episode on UTc 2021 September 25–28,in a series of four *** observations were carried out in the band of 1.0–1.5 Ghz by using the center beam of the L-band 19-beam *** monitored the source in sixteen1 hr sessions and one 3 hr session spanning 23 *** the bursts were detected during the first four *** this first paper of the series,we perform a detailed morphological study of 624 bursts using the two-dimensional frequencytime“waterfall”plots,with a burst(or cluster-burst)defined as an emission episode during which the adjacent emission peaks have a separation shorter than 400 *** duration of a burst is therefore always longer than 1 ms,with the longest up to more than 120 *** emission spectra of the sub-bursts are typically narrow within the observing band with a characteristic width of~277 *** center frequency distribution has a dominant peak at about 1091.9 mhz and a secondary weak peak around 1327.9 *** bursts show a frequencydownwarddrifting *** on the drifting patterns,we classify the bursts into five main categories:downward drifting(263)bursts,upward drifting(3)bursts,complex(203),no drifting(35)bursts,and no evidence for drifting(121)*** are introduced based on the emission frequency range in the band(low,middle,high and wide)as well as the number of components in one burst(1,2,or multiple).We measured a varying scintillation bandwidth from about 0.5 mhz at 1.0 Ghz to 1.4 mhz at 1.5 Ghz with a spectral index of 3.0.

关键词： (stars:)pulsars:general Physical Data and Processes stars:individual(fRb 20201124A)

Ion motion effects on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration

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high Power Laser Science and Engineering 2014年第2期2卷 1-7页

作者： W.P.wang X.m.Zhang X.f.wang X.y.Zhao j.c.xu y.h.yu L.Q.yi y.Shi L.G.Zhang T.j.xu c.Liu Z.K.Pei b.f.Shen State Key Laboratory of high field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

The effects of ion motion on the generation of short-cycle relativistic laser pulses during radiation pressure acceleration are investigated by analytical modeling and particle-in-cell simulations. Studies show that the rear part of the transmitted pulse modulated by ion motion is sharper compared with the case of the electron shutter only. In this study, the ions further modulate the short-cycle pulses transmitted. A 3.9 fs laser pulse with an intensity of 1.33×1021W cm-2is generated by properly controlling the motions of the electron and ion in the simulations. The short-cycle laser pulse source proposed can be applied in the generation of single attosecond pulses and electron acceleration in a small bubble regime.

关键词： radiation pressure acceleration short-cycle pulses particle-in-cell simulations.

Synchronous optimization of strengths, ductility and corrosion resistances of bulk nanocrystalline 304 stainless steel

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journal of materials Science & Technology 2020年第2期37卷 161-172页

作者： S.G.wang m.Sun S.y.Liu X.Liu y.h.xu c.b.Gong K.Long Z.D.Zhang Shenyang National Laboratory.f.r materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Structural materials usually suffer from several attacks during their service,such as tension,fatigue and *** is necessary to synchronously improve these properties for their lightweight and longlifetime,but corrosion resistance and ductility are generally inverse correlation with strength,it is very difficult to simultaneously optimize all three ***,bulk nanocrystalline 304 stainless steel(bN-304SS)produced by severe rolling technology possessed the larger yield and ultimate tensile strengths with sufficient elongation(>40%)during tensile test,the larger saturation stress and longer lifetime during low-cycle fatigue,the enhanced uniform and pitting corrosion resistances during fiveday immersion test in 6 mol/L hcl,the lowered stress corrosion cracking(Scc)susceptibility with larger yield(~2.40 GPa)and ultimate tensile(~2.66 GPa)strengths,and enough elongation(>30%)during stress corrosion in comparison with conventional polycrystalline 304 stainless steel(cP-304 SS)*** uniform and pitting corrosion resistances of fractured bN-304SS were enhanced in comprsion with those of fractured cP-304 SS during seven-day immersion test in 1 mol/L *** results demonstrated the strengths,ductility and corrosion resistances of bN-304SS can be simultaneously optimized by severe rolling *** improved results of bN-304SS in different disciplines were understood by its valence electron configurations rather than traditional microstructural parameters.

关键词： Stainless steel Pitting corrosion Stress corrosion Tensile properties Low-cycle fatigue Severe rolling technology

Long-period grating inscription on polymer functionalized optical microfibers and its applications in optical sensing

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Photonics Research 2016年第2期4卷 45-48页

作者： Z.y.xu y.h.Li L.j.wang joint Institute for measurement Science Tsinghua University Shanghai Institute of Laser Plasma State Key Laboratory of Precision measurement Technology and Instruments Tsinghua University

We demonstrated long-period grating(LPG) inscription on polymer functionalized optical microfibers and its applications in optical sensing. Optical microfibers were functionalized with ultraviolet-sensitive polymethyl methacrylate jackets and, thus, LPGs could be inscribed on optical microfibers via point-by-point ultraviolet laser exposure. for a 2 mm long microfiber LPG(mLPG) inscribed on optical microfibers with a diameter of 5.4 μm, a resonant dip of 15 d b at 1377 nm was observed. This mLPG showed a high sensitivity of strain and axial force, i.e.,-1.93 pm∕με and-1.15 pm∕μN, respectively. Although the intrinsic temperature sensitivity of the LPGs is relatively low, i.e.,-12.75 pm∕°c, it can be increased to be-385.11 pm∕°c.b. appropriate sealing. benefiting from the small footprint and high sensitivity, mLPGs could have potential applications in optical sensing of strain,axial force, and temperature.

关键词： mLPG Long-period grating inscription on polymer functionalized optical microfibers and its applications in optical sensing

What is going on in magnesium alloys？

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journal of materials Science & Technology 2018年第2期34卷 245-247页

作者： X.j. wang D.K. xu R.Z. Wu X.b. chen Q.m. Peng L. jin y.c. Xin Z.Q. Zhang y. Liu X.h. chen G. chen K.K. Deng h.y. wang School of materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Key Laboratory of Superlight materials & Surface Technology (ministry of Education) Harbin Engineering University Harbin 150001 China School of Engineering RMIT University City Campus Carlton VIC 3053 Australia State Key Laboratory of metastable materials Science and Technology Yanshan University Qinhuangdao 066004 China National Engineering Research center of Light Alloy Net forming Shanghai Jiao Tong University Shanghai 200240 China college of materials Science and Engineering Chongqing University Chongqing 400030 China Key Lab of Electromagnetic Processing of materials Ministry of Education Northeastern UniversityShnenyang 110819China Key Laboratory of Lightweight and high Strength Structural materials of jiangxi Province Nanchang University Nanchang 330031 China School of chemical Engineering and Technology Tianjin University Tianjin 300350 China Shanxi Key Laboratory of Advanced magnesium-based materials Taiyuan University of Technology Taiyuan 030024 China Key Laboratory of Automobile materials of ministry of Education & School of materials Science and Engineering Jilin University Changchun 130025 China

china has been developed into one of the most active regions in terms of both fundamental and applied research on magnesium （mg） and its alloys in the world from a solid base laid by its prominent metallurgist and materials scientists over the past decades. Nowadays, a large number of young-generation researchers have been inspired by their predecessors and become the key participants in the fields of mg alloys, which consequently led to the establishment of china youth Scholar Society.f.r magnesium Alloys Research in 2015. Since then, the first two china youth Scholars Symposiums on mg Alloys Research had been held at harbin （2015） and chongqing （2016） china, respectively. A number of crucial research inter- ests related to fundamental and applied mg research were discussed at the conferences and summarized in this short perspective, aiming to boost far-reaching initiatives for development of new mg-based materials to satisfy the requirements for a broad range of industrial employments. herein, four main aspects are included as follows： i） Plastic deformation mechanism and strengthening strategy, ii） Design and development of new mg-based materials, iii） Key service properties, and iv） New processing technologies.

关键词： mg alloys Plastic deformation Strengthening Alloying design high performance corrosion fatigue behavior creep Processing technologies Purification