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A Study on Cosmogenic Nuclides in the Jilin Meteorite and Its Irradiation History

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Acta Geochimica 1982年第4期1卷 421-434页

作者：欧阳自远 G.HEUSSEr Institute of Geochemistry Academia Sinica max-planck-Institut für kernphysik

44 samples of the Jilin meteorite were analyzed by various laboratories for spallogenic,radiogenic,and trapped rare gases.A non-uniform distribution has been found for the raregases of different *** have been found correlations among the spallogenic raregases,with apparent depth effects.43 samples were analyzed for their cosmogonic radionuc-lides;Co,;Al,;Cl,;K,;Mn,;Mn,and;*** have been found between;Co and;Mn and between;Co and;*** Jilin meteorite has a complex history of cosmic-ray *** to the two-stage model and the other fragments have a burying depthtwo stages,T;=*** T;=*** burying depth of all samples in the parentbody can be obtained by the content of;*** meteorite No.1 is located 20—142 cm fromthe surface,No.4 ranges from 106—134 cm,and the other fragments have a burying depthbetween 15 and 150 *** equation of the reference plane for the surface of the 1-stageJilin meteoroid is 0.24x+0.81y+0.53z+0.5=*** can also be made of;Co to determinethe burying depth of all samples in the 2-stage Jilin meteoroid（under a geometry of 4π）,and further to restore the preatmospheric form and size of the parent *** its at-mospheric passage,the Jilin had an ablation rate of ca.30%.On the basis of the two-stagemodel and the concentration of;Ne and;Co in the samples,we propose a scheme to restorethe relative position of all samples in the parent body.12 sample-distribution regions can besketched *** can be restored the relative position of all the samples in the parent bodyduring the two stages.

关键词： A Study on Cosmogenic Nuclides in the Jilin Meteorite and Its Irradiation History

Cooling rates in the shock veins of chondrites: constraints on the (Mg,Fe)_2SiO_4 polymorph transformations

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Science China Earth Sciences 1998年第5期41卷 522-528页

作者：陈鸣谢先德 A.ElGoresy B.Wopenka T.G.Sharp Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China max-planck-institutfür kernphysik Heidelberg Germany Department of Earth and Planetary Sciences Washington University St.Louis USA Department of Geology Arizona State University Tempe USA

The occurrence of γ phase, a high\|pressure polymorph of olivine （α phase）, in the shock veins of Si\| xiangkou chondrite was due to a greater cooling rate （>10 000℃·s -1 ） in the veins. Because γ phase partially reverted to β phase and no back\|transformation from β phase to α phase took place, the shock veins of Peace river chondrite with a cooling rate of 1 000\2 000℃·s -1 contain a great amount of β phase. In the shock veins of Mbale chondrite with a cooling rate of rity of γ phase reverted to α phase. The heat dissipation in shock veins took place after a stage of shock compression of chondrite parent body, and the parent body was broken into fragmental pieces. Cooling rate in the shock veins constrained the back\|transformations of （Mg,Fe）\-2SiO\-4 high\|pressure polymorphs.

关键词： chondrite shock vein (Mg Fe)\-2SiO\-4 polymorph transformation cooling rate.

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

A STUDY ON COSMOGENIC NUCLIDES IN JILIN METEOrITE AND ITS TWO-STAGE IrrADIATION HISTOrY

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Science China Chemistry 1984年第3期 320-332页

作者：欧阳自远,G.霍依兹,M.赫布纳,T.克尔斯顿 Guiyang Institute of Geochemistry Academia Sinica max-planck-Institut für kernphysik Heidelberg max-planck-Institut für kernphysik Heidelberg max-planck-Institut für kernphysik Heidelberg

Forty-four burk samples of the H chondrite Jilin have been analysed for their contents ofspallogenic, trapped and radiogenic noble gases, and thirty-five samples have been determinedfor their radiocosmogenic nuclides. The Jilin meteorite has an extreme complicated history ofcosmic-ray irradiation. In the 1st-stage, the Jilin meteorite might be located between 0.2--2mbelow the surface of the parent body travelling about 8 m. y. in space and under a geometryof 2π subjected to the radiation of cosmic-ray. According to the data of60Co dating the burialdepth of all samples in the 2nd-stage can be determined and the preatmospheric form andsize of the parent body can be restored （under a geometry of 4π）. The result of this recon-struction is that, the 2nd-stage has a nearly spheric form, with a radius of 85±5 cm, weighing9.7±1.7 Ts. The position of the center of the preatmospheric body is: X=55, Y=55 andZ=39. Jilin meteorite No.1 is located at the center of the parent body and is surroundedwith the fragments. The ablation rate is estimated at about 30%. We have proposed a new modelof the two-stage irradiation, and based on the contents of21Ne-60Co in the samples, a classificationscheme can be worked out for the restoration of relative position of the samples within theparent body.

关键词： body A STUDY ON COSMOGENIC NUCLIDES IN JILIN METEOrITE AND ITS TWO-STAGE IrrADIATION HISTOrY

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

THE CHEMICAL COMPOSITIONS OF MINErALS IN QINGZHEN METEOrITE AND ITS GEOCHEMISTrY SIGNIFICANCE

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Science China Chemistry 1989年第8期32卷 995-1002页

作者：侯渭欧阳自远 A.EL.GOrESY H.YABUKI Guiyang Institute of Geochemistry Academia Sinica max-planck Institute Fur kernphysik Heidelberg West Germany Institute of Physical and Chemical research Japan

The chemical compositions of silicate minerals, sulphide minerals and metal Fe-Ni in theQingzhen meteorite were measured by the microprobe analyses. Based upon these chemicalcompositions, the cosmochemical behaviour and characteristics of the existing forms of themajor elements in the Qinzhen meteorite have been discussed. These characteristics show thatunder the S-rich, O-poor, and strongly reducing conditions, the light metal elements, such asCa, Mg, K, Na may form sulphide, and metal Fe-Ni may contain Si and P. However, we con-sider that the light metal-sulphide can be stable in the lower mantle and there are some Siand P in the Fe-Ni core. Finally, an earth core-mantle model is established, where the Fe-Ni core contains some Si and P; the lower mantle is composed of Mg-rich silicate, SiO_2 andsulphide; the upper mantle, of silicate and oxide.

关键词： enstatite chondrite Qingzhen meteorite earth core-mantle model

rEE and Other Trace Element Chemistry of Oldhamite(CaS)in the Qingzhen Chondrite(EH3)and Their Genetic Implications

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Chinese Journal Of Geochemistry 1993年第4期12卷 317-327页

作者：陈永亨王道德 ErNST PErNICKA Institute of Geochemistry(Guangzhou Branch) Academia SinicaGuangzhou510640 max-planck-Institut fur kernphysik 6900 HeidelbergGermany

Instrumental neutron activation analysis(INAA) of 14 single oldhamite grains separated from the Qingzhen chondrite (EH3) for refractory(La,Ce,Sm ,Eu,Yb,Lu,Ca,Sc,Hf, and Th),volatile (Na,Cr,Zn,Se,Br,etc.)and siderophile elements (Fe,Ni,Co,Ir,Au ,and As) revealed that oldhamite is highly rich in refractory *** mineral serves as the principal carrier of rEE and contains about 80% of the rEEs in the Qingzhen enstatite chondrite .Furthermore, the large enrichment of LrEE relative to HrEE is noticed in oldhamite from the Qingzhen .In general, the oldhamite from metal-sulfide assemblages is richer in rEE than that from the matrix,i.e.,the earlier the oldhamite grains condensed, the richer they are in rEE. *** is also rich in vol-atile elements such as Se,Br, *** terms of the distribution of trace elements in oldhamitc from the Qingzhen ,the chondrite is srggested to have resulted from high-temperature condensation of solar nebula.

关键词：球粒状陨石硫化物示踪元素稀土元素中子活化分析顽辉石

Double-electron capture in slow Ar16+--Ne collisions

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Double-electron capture in slow Ar16+--Ne collisions

DEPTH DISTrIBUTION OF COSMOGENIC NUCLIDES IN BOrING COrE SAMPLES OF JILIN METEOrITE AND ITS COSMIC rAY IrrADIATION HISTOrY

第十五届全国原子与分子物理学术会议

作者： D.Fischer r.Ginzel S.Bernitt K.U.Khnel A.Krauss J.r.Crespo López-Urrutia r.Moshammer J.Ullrich max-planck-Institut fr kernphysik

When slow highly charged ions collide with neutral atoms one or several electrons are transferred with high probability from the target atoms into the highly charged *** is well known that few-electron capture results...

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Science China Mathematics 1987年第8期 885-896页

作者：欧阳自远,范彩云,易惟熙,王先彬,F. BEGEMANN,T. KErSTEN,G. HEUSSEr,E. PErNICKA Institute of Geochemistry Academia Sinica Guiyang Institute of Geochemistry Academia Sinica Guiyang Institute of Geochemistry Academia Sinica Guiyang Lanzhou Institute of Geology Academia Sinica max-planck-Institut für Chemie Mainz max-planck Institut Für kernphysik Heidelberg max-planck Institut Für kernphysik Heidelberg max-planck Institut Für kernphysik Heidelberg

Two boring cores were successfully sampled from the Jilin No. 1 meteorite in such a way that they were kept parallel or perpendicular to the surface of the 1st stage parent body, but across the center of the 2nd stage parent body. Cosmogenic nuclides(3He,20, 21, 22Ne,22Na,26Al,53Mn,50Co), radiogenic gases and trapped noble gases in the two cores have been studied in great detail, which has confirmed the two-staged cosmic ray irradiation history proposed by the authors as being typical of the Jilin Meteorite, and also justified our previous models regarding the ages, shapes and sizes of the two parent bodies related to the two stages as well as the emplacement of various samples. Investigations of spallogenic, radiogenic and trapped gases reveal that the periodic heating by the sun of the 2nd-stage parent body was responsible for the gas loss from the body while it was moving in the inter-planet spaces. The relative positions of the No.2 meteorite in the parent bodies of the two stag

关键词： body DEPTH DISTrIBUTION OF COSMOGENIC NUCLIDES IN BOrING COrE SAMPLES OF JILIN METEOrITE AND ITS COSMIC rAY IrrADIATION HISTOrY