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Ultra-high energy cosmic neutrinos from gamma-ray bursts

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Fundamental Research 2024年第1期4卷 51-56页

作者： Yanqi Huang bo-qiang ma School of Physics Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China

Based on the recent association of IceCube TeV and PeV neutrino events with gamma-ray bursts(GRBs)by considering the Lorentz violation of neutrinos,we provide a new estimate on the GRB neutrino flux with a more significant result compared to the previous constraint by the IceCube *** these 24 neutrino“shower”events above 60 TeV,12 events are associated with *** a result is compatible with the prediction from GRB fireball *** of track events provides a consistent result with the shower events to associate high energy cosmic neutrinos with GRBs under the same Lorentz violation features of *** also make a background estimation and reveal GRBs as a significant source for the ultra-high energy IceCube neutrino *** work supports the Lorentz violation and CPT-violation of neutrinos,indicating new physics beyond relativity.

关键词： Cosmic neutrino Gamma-ray burstLorentz invariance violation Neutrino and anti-neutrino asymmetry CPT-violation of neutrinos

A concise proof of Benford's law

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Fundamental Research 2024年第4期4卷 841-844页

作者： Luohan Wang bo-qiang ma School of Physics Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China

This article presents a concise proof of the famous Benford's law when the distribution has a Riemann integrable probability density function and provides a criterion to judge whether a distribution obeys the *** proof is intuitive and elegant,accessible to anyone with basic knowledge of calculus,revealing that the law originates from the basic property of human number *** criterion can bring great convenience to the field of fraud detection.

关键词： Benford's law First-digit law Significant digit law Proof Criterion

Axion-Photon Conversion of LHAASO Multi-TeV and PeV Photons

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Chinese Physics Letters 2023年第1期40卷 19-22页

作者：张光帅马伯强 School of Physics Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China

The Large High Altitude Air Shower Observatory(LHAASO)has reported the detection of a large number of multi-Te V-scale photon events also including several Pe V-scale gamma-ray-photon events with energy as high as 1.4 Pe *** possibility that some of these events may have extragalactic origins is not yet *** we propose a mechanism for the traveling of very-high-energy and ultra-high-energy photons based upon the axionphoton conversion scenario,which allows extragalactic above-threshold photons to be detected by observers on the *** show that the axion-photon conversation can serve as an alternative mechanism,besides the threshold anomaly due to Lorentz invariance violation,for the very-high-energy features of the newly observed gamma ray burst GRB 221009A.

关键词： traveling Lorentz galactic

Light speed variation from active galactic nuclei

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Science Bulletin 2020年第4期65卷 262-266页

作者： Hao Li bo-qiang ma School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Center for History and Philosophy of Science Peking UniversityBeijing 100871China

According to Einstein’s relativity,the speed of light is a constant in free ***,it is speculated from quantum gravity that the light speed may receive a correction in powers of E=EPl,where E is the energy of the photon and EPl?■≈1.22×10^19 GeV is the Planck *** the light speed might be energy dependent due to the Lorentz invariance violation(see,e.g.,Refs.[1–6]).Such speed variation is very tiny and can hardly be detected on the *** was suggested by Amelino-Camelia et al.[7]that photons from gamma-ray bursts(GRBs)can be used to detect the light speed variation.

关键词： red PKS 304 活动星系核光变曲线

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质子偶素:实验发现及理论预言

科学通报 2024年第31期69卷 4620-4624页

作者：马伯强北京大学物理学院北京100871

2024年4月9日,北京谱仪Ⅲ(Beijing SpectrometerⅢ,BESⅢ)合作组[1]在Physical Review Letter发表了一篇文章,报道了实验组利用北京正负电子对撞机(Beijing Electron Positron Collider,BEPC)产生的100亿个粲夸克偶素事例,分析由粲夸克偶素衰变到一个光子和三对正负介子对的衰变过程,通过重建三对正负介子对的不变质量并由两个共振态结构X(1840)和X(1880)来拟合数据(图1),发现X(1880)的统计显著性超过10倍标准偏差的偏离.

关键词：粲夸克偶素 BESⅢ 不变质量衰变过程理论预言统计显著性标准偏差北京谱仪Ⅲ

LHAASO discovery of highest-energy photons towards new physics

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Science Bulletin 2021年第22期66卷 2254-2256,M0003页

作者： Chengyi Li bo-qiang ma School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China

Ultrahigh-energy(UHE)photons up to 1.4 peta-electronvolts have been observed by new cosmic-ray telescope in China[1]–a hint that Lorentz invariance might break down at the Planck-scale level[2].As one of the most sensitive gamma-ray detector arrays currently operating in the UHE band,the Large High Altitude Air Shower Observatory(LHAASO)recently reported large numbers of gamma-ray photons with energies larger than 100 TeV from twelve cosmic accelerators within the Milky Way[1],including the most high-energetic c-ray detected at about 1:4 *** observation of such high-energy lights from space can be used not only to investigate the long-lasting puzzle of the origin of UHE cosmic rays and their acceleration mechanism in the extreme regions of the Universe,but can provide also the unique and crucial opportunity in testing fundamental concepts of physics,such as one basic symmetry underlying Einstein’s relativity–Lorentz invariance[2].

关键词： Lorentz invariance symmetry

Bethe-Heitler lepton pair production in the deuteron breakup reaction

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Chinese Physics C 2024年第1期48卷 94-109页

作者：蔡孟初刘天博马伯强 School of Physics Peking UniversityBeijing 100871China Key Laboratory of Particle Physics and Particle Irradiation(MOE) Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China Center for High Energy Physics Peking UniversityBeijing 100871China

We study the lepton pair production via the Bethe-Heitler mechanism in the deuteron breakup *** complete seven-fold differential cross section is calculated with final state interactions taken into *** deuteron bound state is described by a relativistic covariant deuteron-nucleon *** numerical results indicate that the differential cross section is highly dependent on the lepton's azimuthal angle in regions of small polar angles and exhibits sharp peaks in the distribution over the invariant mass of the generated lepton pair or the two nucleons in the final *** demonstrate that such a nearly singular feature originates from the collinearity between the produced lepton or antilepton and the incident photon,and it is physically regularized by the lepton mass in our *** final state interaction between the knocked-out nucleon and recoil nucleon redistributes the differential cross section over the missing momentum,with a significant enhancement at a large missing momentum and a suppression in the intermediate *** a further decomposition of the final state interaction contribution,It is found that the on-shell term dominates the near quasi-elastic region,while the off-shell term dominates the other ***,we examine the contribution from the interference between the proton amplitude and neutron amplitude,which,as expected,is found negligible even if the proton-neutron rescattering is *** results of this study can serve as inputs for the analysis and background estimation of multiple exclusive measurements at Jefferson Lab and future electron-ion colliders.

关键词： Bethe-Heitler process deuteron breakup final state interactions

magnetron sputtered nickel oxide with suppressed interfacial defect states for efficient inverted perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 348-355页

作者： Guoqiang ma Qin Tan Zhaoning Li Jingwei Xiu Jiafeng Wang Tianle Cheng Dong He qiang Sun Xuhang ma Francesco Lamberti Zhubing He Department of materials Science and Engineering Institute of Innovative Materials (I2M) Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation (FSSEG)Southern University of Science and Technology (SUSTech) Core Research Facilities Southern University of Science and Technology Department of Chemical Sciences Department of Industrial Engineering University of Padova

Widely used spin-coated nickle oxide （NiOx） based perovskite solar cells often suffer from severe interfacial reactions between the NiOxand adjacent perovskite layers due to surface defect states,which inherently impair device performance in a long-term view,even with surface molecule *** this study,we developed high-quality magnetron-sputtered NiOxthin films through detailed process optimization,and compared systematically sputtered and spin-coated NiOxthin film surfaces from materials to *** sputtered NiOxfilms exhibit improved crystallinity,smoother surfaces,and significantly reduced Ni3+or Ni vacancies compared to their spin-coated ***,the interface between the perovskite and sputtered NiOxfilm shows a substantially reduced density of defect *** solar cells （PSCs） fabricated with our optimally sputtered NiOxfilms achieved a high power conversion efficiency （PCE） of up to 19.93%and demonstrated enhanced stability,maintaining 86.2% efficiency during 500 h of maximum power point tracking under one standard sun ***,with the surface modification using (4-(2,7-dibromo-9,9-dimethylacridin-10（9H）-yl)butyl)p hosphonic acid （DmacPA）,the device PCE was further promoted to 23.07%,which is the highest value reported for sputtered NiOxbased PSCs so far.

关键词： Nickle oxide magnetron sputter Defect Stability Perovskite solar cell

FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： Yuhui Kou Zongxue Jin Yusong Yuan bo ma Wenyong Xie Na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina National Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons