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500 个结果
  • 简介:Veryrecently,BelleannouncedtheirobservationofΥ(5S)!bJ!(J=0;1;2),indicatingthattheΥ(5S)!bJ!decaysalsohavelargedecaywidths,i.e.,themeasuredbranchratiosofΥ(5S)!bJ!are<3:410??3,(1:640:23+0:30??0:22)10??3,and(0:570:220:07)10??3withJ=0;1;2,respectively[1].ItshouldbenoticedthateventhoughthetreelevelcontributionstoΥ(5S)!bJ!(J=0;1;2)shouldbestronglysuppressedduetotheOkubo-Zweig-Iizuka(OZI)rule,suchlargedecaywidthsareobserved,whichagaininspiresourinterestinunderstandingsuchquantities.Inthiswork,weproposethatthecontributionfromthehadronicloopshouldbeconsideredinstudyingΥ(5S)!bJ!.

  • 标签: LOOP LOOP BE OUR IT
  • 简介:隐藏的对称和一个无限的集合广告5S5上的格林Schwarz超弦的非局部的保存水流被Bena等指出了。在这篇论文,我们证明在MaurerCartan方程和运动的方程之间双的农夫在格林Schwarz超弦的moduli空格给隐藏的对称。因此由扭曲的转变vielbeins,我们能表示纸的水流[我。Bena,J。Polchinski,和R。Roiban,Phys。加快。D69(2004)046002]作为宽松的连接由一唯一光谱参数。

  • 标签: 超粒子 Hodge对偶 隐藏对称 分子物理学
  • 简介:在这篇论文,一些组Ext_A~(s,t)(Z_p,Z_p)与专业化s和t,第一到5月被计算光谱顺序。然后,我们使用亚当斯光谱在稳定的homotopy证明过滤s+的一个新重要家庭的存在是5的顺序范围π_(p~nq+(s+3)pq+(s+1)q-5)组织被代表的S(直到非零数量)由β_(s+2)b_0h_n∈Ext_A~(s+5,p~nq+(s+3)pq+(s+1)q+s)(Z_p,Z_p)在亚当斯光谱,定序5是的p≥一个素数,n≥3,0≤s

  • 标签: 球面 稳定同伦 非平凡积 σ域流
  • 简介:Asimplemethodisappliedtocalculatingtheisotopeshifts(ISs)on5S1/2→4D3/2,5/2transitionsof87,88Sr+.FirstwehavecalculatedtheISsoflowertransitionsonaseriesofalkali-likesystemssuchasB2+,Ca+andBa+,whichareinagreementwithotherworks.ThentheISson5S1/2→4D3/2,5/2transitionsof87,88Sr+,whichareusefultostudytheSr+opticalfrequencystandard,areevaluated.

  • 标签: 原子物理 同位素位移 5S1/2→4D3/2 5/2 精细结构
  • 简介:ErdǒsandSósconjecturedin1963(see[1],Problem12in247)thateverygraphGonnverticeswithsizee(G)>1/2n(κ-1)containseverytreeTofsizek.Inthispaper,weprovetheconjectureforgraphswhosecomplementscontainnocyclesoflength4.

  • 标签: 顶点集 曲线图 图论 包裹 树状图
  • 简介:在Diff(S1)/S之间的关系1并且磁盘上的一价的分析函数的空间被阐明并且出现为彻底的近似的卷提供上面的界限给一个无限维的空格的分析submanifold。在superdisk上的一价的superanalytic功能的系列扩大的系数的最大的大小被推断。

  • 标签: 单叶函数 superdisk 解析函数空间 无穷维空间 扩展系数 流形
  • 简介:Inthispaper,withPoincare’sformalism,andanindirectmethod,thecanonicalformsofthegeneralizedequationsofmotionduetoNielsenandCenovofaholonomicdynamicalsysteminthevelocity-phasespaceandtheacenleration-phasespaceareobtainedintermsofthePoincareparameters.

  • 标签: HOLONOMIC DYNAMIC SYSTEM Nielsen’s EQUATIONS of
  • 简介:作者在C上给围住的双线性的表格的Fourier变换的描述*(S1)×C*(二基础半的S2)以乔丹组织S1和S2*-representations,hemimogeneous随机域,并且象一样微弱地,harmonizable随机S回答1和S2直到Hilbert空格。

  • 标签: 双线性 半群 数学理论 计算方法
  • 简介:AnewlayeredCu-basedoxychalcogenideBa3Fe2O5Cu2S2hasbeensynthesizedanditsmagneticandelectronicpropertieswererevealed.Ba3Fe2O5Cu2S2isbuiltupbyalternativelystacking[Cu2S2]2-layersandironperovskiteoxide[(FeO2)(BaO)(FeO2)]2-layersalongthecaxisthatareseparatedbybariumionswithFe3+fivefoldcoordinatedbyasquare-pyramidalarrangementofoxygen.Fromthebondvalencearguments,weinferredthatinlayeredCuCh-based(Ch=S,Se,Te)compoundsthe+3cationinperovskiteoxidesheetprefersasquarepyramidalsite,whilethelowervalencecationprefersthesquareplanarsites.Thestudiesonsusceptibility,transport,andopticalreflectivityindicatethatBa3Fe2O5Cu2S2isanantiferromagneticsemiconductorwithaNe′eltemperatureof121Kandanopticalbandgapof1.03eV.Themeasurementofheatcapacityfrom10Ktoroomtemperatureshowsnoanomalyat121K.TheDebyetemperatureisdeterminedtobe113K.TheoreticalcalculationsindicatethattheconductionbandminimumispredominantlycontributedbyO2pand3dstatesofFeionsthatantiferromagneticallyarrangedinFeO2layers.TheFe3dstatesarelocatedatlowerenergyandresultinanarrowbandgapincomparisonwiththatoftheisostructuralSr3Sc2O5Cu2S2.

  • 标签: 钙钛矿型氧化物 铁磁半导体 光学带隙 德拜温度 电子性质 阳离子
  • 简介:TheauthorfirstreviewstheclassicalKorninequalityanditsproof.FollowingrecentworksofS.Kesavan,P.Ciarlet,Jr.,andtheauthor,itisshownhowtheKorninequalitycanberecoveredbyanentirelydifferentproof.ThisnewproofhingesonappropriateweakversionsoftheclassicalPoincar'eandSaint-Venantlemma.Infine,bothproofsessentiallydependonacruciallemmaofJ.L.Lions,recalledatthebeginningofthispaper.

  • 标签: Korn不等式 证明 庞加莱 作者 引理
  • 简介:TheextendedcanonicalNoetheridentitiesandcanonicalfirstNoethertheoremderivedfromanextendedactioninphasespaceforasystemwithasingularLagrangianareformulated.UsingthesecanonicalNoetheridentities,itcanbeshownthattheconstraintmultipliersconnectedwiththefirst-classconstraintsmaynotbeindependent,soaquerytoaconjectureofDiracispresented.BasedonthesymmetrypropertiesoftheconstrainedHamiltoniansysteminphasespace,acounterexampletoaconjectureofDiracisgiventoshowthatDirac'sconjecturefailsinsuchasystem.WepresenthereadifferentwayratherthanCawley'sexamplesandother'sonesinthatthereisnolinearizationofconstraintsintheproblem.Thisexamplehasafeaturethatneithertheprimaryfirst-classconstraintsnorsecondaryfirst-classconstraintsaregeneratorsofthegaugetransformation.

  • 标签: 约束汉密尔顿函数 规范对称 迪拉克猜想 量子场论
  • 简介:S是幺半群含有零元0≠1,且S-系为S0-Act中的对象,本文引进伪投射S-系,刻划了伪投射S-系的一些性质和特征.

  • 标签: 可收缩 伪投射S-系 幺半群