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Discovery potential of the Glashow resonance in an air shower neutrino telescope

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Chinese Physics C 2024年第8期48卷 266-275页

作者： Guo-Yuan Huang School of Mathematics and Physics China University of GeosciencesWuhan 430074China max-planck-institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany

The in-ice or in-water Cherenkov neutrino telescope,such as IceCube,has already proved its power in measuring the Glashow resonance by searching for the bump around E_(ν)=6.3PeV arising from the W-boson *** are many proposals for the next few decades for observations of cosmic tau neutrinos with extensive air showers,also known as tau neutrino *** air shower telescope is,in principle,sensitive to the Glashow resonance via the channel W→τν_(τ)followed by the tau decay in the air(e.g.,TAMBO,which has a geometric area of approximately 500km^(2)).Using a thorough numerical analysis,we find that the discovery significance can be up to 90%with a TAMBO-like setup if PeV neutrinos primarily originate from neutron decays,considering the flux parameters measured by IceCube as the *** presence of new physics affecting the neutrino flavor composition can also increase the ***,if ultrahigh-energy neutrinos are dominantly produced from meson decays,it will be statistically difficult for an advanced proposal such as TAMBO to discriminate the Glashow resonance induced byν¯e from the intrinsicντ/ν¯_(τ)*** have identified several limitations for such advanced telescopes,in comparison with the in-ice or in-water telescope,when measuring resonances:(i)a suppressed branching ratio of 11%for the decay W→τν_(τ);(ii)the smearing effect and reduced acceptance because the daughter neutrino takes away(y)∼75%of the energy from the W decay;and(iii)a large attenuation effect for Earth-skimming neutrinos with the resonance.

关键词： Ultrahigh-energy neutrinos Neutrino telescopes Glashow resonance

Influence of symmetric and asymmetric rolling on texture evolution of work-hardened AA 5xxx aluminium alloy

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Transactions of Nonferrous Metals Society of China 2024年

作者： Matja? Godec Stefan Zaefferer Jakob Kraner ?rtomir Donik Irena Paulin institute of Metals and Technology max-planck-institut für Eisenforschung， max-planck-Strasse 1 Impol 2000 d.d.， Partizanska cesta 38

The textures and microstructures of hot- and cold-rolled sheets of an AA 5454 aluminium alloy were studied， with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling. Scanning electron microscopy with electron-backscatter diffraction was used to monitor the development of the microstructure in the differently deformed and additionally annealed samples. Details of the formations and transformations of individual texture components occurring during the rolling processes were observed and discussed. The average grain sizes， textures and mechanical properties were correlated and explained for the symmetric and asymmetric cold-rolled samples. The asymmetric rolling is beneficial in terms of deep drawability because it reduces the planar anisotropy of the annealed material due to the decrease of the Cube， Goss， rotated Cube and η- fibre texture components and the same time strengthens X1- and X2-fibre texture components which are shear texture components and improve deep drawability. During the asymmetric cold rolling， the temperature increases due to friction， triggering recrystallisation processes and leading to larger grains. It was also confirmed that asymmetric cold rolling uses less rolling force and consequently less energy to produce a final material with better formability， particularly earing.

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Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： Andreas Döpp Ludwig-maximilian-Universität München Am Coulombwall 185748GarchingGermany max planck institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Energy enhancement of laser-driven ions by radiation reaction and Breit-Wheeler pair production in the ultra-relativistic transparency regime

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High Power Laser Science and Engineering 2024年第1期12卷 60-73页

作者： Shikha Bhadoria Mattias Marklund Christoph H.Keitel max-planck-institut für Kernphysik HeidelbergGermany Department of Physics University of GothenburgGöteborgSweden

The impact of radiation reaction and Breit±Wheeler pair production on the acceleration of fully ionized carbon ions driven by an intense linearly polarized laser pulse has been investigated in the ultra-relativistic transparency *** initial expectations, the radiation reaction and pair production at ultra-high laser intensities are found to enhance the energy gained by the ions. The electrons lose most of their transverse momentum, and the additionally produced pair plasma of Breit±Wheeler electrons and positrons co-streams in the forward direction as opposed to the existing electrons streaming at an angle above zero degree. We discuss how these observations could be explained by the changes in the phase velocity of the Buneman instability, which is known to aid ion acceleration in the breakout afterburner regime, by tapping the free energy in the relative electron and ion streams. We present evidence that these non-classical effects can further improve the highest carbon ion energies in this transparency regime.

关键词： ion acceleration quantum electrodynamic effects

Cobalt Single Atom-Catalyzed formation of LiOH in Li-O_(2)Batteries via the Direct 4-Electron Oxygen reduction Pathway

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CCS Chemistry 2024年第10期6卷 2502-2514页

作者： Kang Huang Hao Wan Zhichao Gong Jianbin Liu Minmin Yan Jun Wu Chunyu Cui Gonglan Ye Karsten reuter Huilong fei Advanced Catalytic Engineering research Center of the Ministry of Education State Key Laboratory for Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082 fritz-Haber-institut der max-planck-Gesellschaft Berlin 14195

The formation of LiOH as the discharge product instead of Li_(2)O_(2)in Li-O_(2)batteries(LOBs)is highly desirable due to the associated drawbacks of Li_(2)O_(2)-based chemistry,which involves the generation of reactive oxygen intermediates responsible for substantial side ***,the current challenge lies in the formation pathway of LiOH,which typically requires the chemical hydrolysis of the hazardous LiO_(2)or Li_(2)O_(2)intermediate,posing risks to the battery ***,we report a direct 4e–electrochemical approach to LiOH enabled by a single atom catalyst(SAC)consisting of CoN_(3)moieties embedded in graphene(CoN_(3)-G),while Li_(2)O_(2)is formed on the metal-free nitrogen-doped graphene(NG).The direct 4e–LiOH pathway significantly reduces the parasitic reactions,resulting in negligible damage to the electrolyte and *** stands in strong contrast to the conventional 2e–Li_(2)O_(2)pathway mediated by NG and the indirect LiOH pathway by MnO_(2).Theoretical calculations further clarify that the presence of CoN_(3)sites enhances the adsorption of oxygen-containing intermediates like*OLiO and*Li_(2)O_(2),promoting the protonation of*Li_(2)O_(2)and the cleavage of the O–O bond to form *** work demonstrates a promising strategy to modulate the reaction pathways in LOBs and broadens the applications of SACs.

关键词： single atom catalyst LiOH Li-O_(2)batteries direct 4-electron oxygen reduction pathway selectivity

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费曼积分作为一类新的特殊函数

Science Bulletin 2024年第7期69卷 859-862页

作者：刘志峰马滟青王辰宇 Zhejiang institute of Modern Physics School of PhysicsZhejiang UniversityHangzhou 310027China School of Physics Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China max-planck-institut für Physik Garching 85748Germany

feynman integrals(fIs)serve as fundamental components of perturbative quantum field *** study of fIs is important for both exploring the mysteries of quantum field theories and their phenomenological applications,particularly in particle physics.A significant amount of effort has been devoted to analytically calculating fIs,with the goal of expressing them as linear combinations of special functions.

关键词： functions. theory. 特殊函数

Ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuALitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China max-planck-institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany GSI Helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology Guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in *** new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 *** compared to the analogue states in its mirror nucleus ^(22)f,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)f mirror pair are determined to be−625(51)keV and−330(51)*** excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field *** mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSrG calculations chiral interactions

The effect of Laves phases and nano-precipitates on the electrochemical corrosion resistance of Mg-Al-Ca alloys under alkaline conditions

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Journal of Magnesium and Alloys 2024年第6期12卷 2447-2461页

作者： Markus felten Veronika Chaineux Siyuan Zhang Ali Tehranchi Tilmann Hickel Christina Scheu Joshua Spille Marta Lipińska-Chwałek Joachim Mayer Benjamin Berkels Marcus Hans Imke Greving Silja flenner Sandra Sefa Daniela Zander Chair of Corrosion and Corrosion Protection RWTH Aachen UniversityAachen 52072 Germany max-planck-institut für Eisenforschung GmbH Düsseldorf 40237 Germany Central facility for Electron Microscopy RWTH Aachen UniversityAachen 52074 Germany Ernst ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich GmbHJülich 52428Germany Mathematical Image and Signal Processing Aachen Institute for Advanced Study in Computational Engineering ScienceRWTH Aachen UniversityAachen 52062 Germany Materials Chemistry RWTH Aachen UniversityAachen 52074 Germany institute of Materials Physics Helmholtz-Zentrum HereonGeesthacht 21502 Germany

The electrochemical corrosion mechanisms of Mg alloys were extensively studied in previous investigations of different chemical com-positions,modified surface states and various electrolyte ***,recent research focused on the active state of Mg dissolution,leading to unresolved effects of secondary phases adjacent to a stableα-solid solution passive *** present study investigates the fundamental electrochemical corrosion mechanisms of three different Laves phases with varying phase morphologies and phase fractions in the passive state of Mg-Al-Ca *** microstructure was characterized by(transmission-)electron microscopy and synchrotron-based transmission X-ray *** electrochemical corrosion resistance was determined with a standard three-electrode setup and advanced in-situ flow cell measurements.A new electrochemical activity sequence(C15>C36>α-Mg>C14)was obtained,as a result of a stable passive layer formation on theα-solid ***,nm-scale Mg-rich precipitates were identified within the Laves phases,which tend to inhibit the corrosion kinetics.

关键词： Laves phase STEM Magnesium Corrosion Passive layer

Data-driven Simulations of Magnetic field Evolution in Active region 11429:Magneto-frictional Method Using PENCIL CODE

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research in Astronomy and Astrophysics 2024年第2期24卷 74-82页

作者： P.Vemareddy Jorn Warnecke Ph.A.Bourdin Indian institute of Astrophysics Sarjapur roadII BlockKoramangalaBengaluru-560034India max-planck-institut für Sonnensystemforschung Justus-von-Liebig-Weg 3D-37077 GöttingenGermany institute of Physics University of GrazUniversitätsplatz 5A-8010 GrazAustria

Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short *** of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal magnetic field evolution using observations of the magnetic field at the photosphere is a fundamental requirement to understanding the origin of transient phenomena from solar active regions(Ars).Using the magneto-friction(Mf)approach,we aim to simulate the coronal field evolution in the solar Ar *** Mf method is implemented in the open source PENCIL CODE along with a driver module to drive the initial field with different boundary conditions prescribed from observed vector magnetic fields at the *** order to work with vector potential and the observations,we prescribe three types of bottom boundary drivers with varying free-magnetic *** Mf simulation reproduces the magnetic structure,which better matches the sigmoidal morphology exhibited by Atmospheric Imaging Assembly(AIA)images at the pre-eruptive *** found that the already sheared field further driven by the sheared magnetic field will maintain and further build the highly sheared coronal magnetic configuration,as seen in Ar ***-driven Mf simulation is a viable tool to generate the coronal magnetic field evolution,capturing the formation of the twisted flux rope and its eruption.

关键词： Sun corona-Sun evolution-Sun magnetic fields-Sun photosphere