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25 个结果
  • 简介:UsingtheefectiveHamiltonianmethod,weanalyzetheB0-ˉB0mixingintheextensionofthestandardmodel(SM)wherebaryonnumberandleptonnumberarelocalgaugesymmetries.ThenumericalresultsindicatethecorrectionfromtheextraparticlestothemassdiferencemBissignificant.Thereisa60%enhancementcomparedtotheSMpredictionformBatmost,whichagreeswiththecurrentexperimentalresult.

  • 标签: 重子数 混合 轻子 有效哈密顿方法 标准模型 计算结果
  • 简介:Thereisagrowingsupportforthelowlyingscalarmesonsf0(500),f0(980),a0(980),and(800)tobegenerateddynamicallyfromtheinteractionofpseudoscalarmesons,whilethecaseofthenextsetofscalarresonancesathigherenergies,f0(1370),f0(1710),K0(1430)ismoreaquestionofdebate.Soisthecaseofthetensorresonancesf2(1270),f′2(1525),K2(1430).AnewperspectiveonthesestateshasbeenofferedinRef.[1]wherethef0(1370)andf2(1270)resonancesareshowntobegeneratedfromtheinteractionprovidedbythelocalhiddengaugeLagrangiansimplementingunitarization.Itisshownthattheideaofthenatureofthesestatesasvectormeson-vectormesoncompositestateshasbeentestedinmanyreactions.Yet,thepermanentdiscussionoftheissuedemandsextrachecksforotherobservablesand,inthissense,theweakdecaysbringanewsourceofvaluableinformationthatshouldservetotestdifferentmodels.

  • 标签: J/Ψ source case SENSE NEXT IDEA
  • 简介:Inthisarticle,wecalculatethecontributionfromthenonfactorizablesofthadronicmatrixelementtothedecayB~0→χc1~π~0withthelight-conequantumchromo-dynamic(QCD)sumrules.Thenumericalresultsshowthatitscontributionisratherlargeandshouldnotbeneglected.Thetotalamplitudesleadtoabranchingfractionwhichisinagreementwiththeexperimentaldatamarginally.

  • 标签: QCD求和规则 衰变 计算结果 强子矩阵元 实验数据 动力学
  • 简介:SAMisanetwork-distributeddatamanagementsystemdevelopedatFermilabforusewithRunIIdata,ItisbeingEmployedbytheD0Experimenttostore,manage,deliver,andtrackprocessingofalldata.Wedescribethedesignandfeaturesofthesystemincludingresourcemanagementanddatatransfermechanisms,WeshowtheoperationalexperienceD0hasaccumulatedtodateincludingdataacquisitionprocessing,andalllevelsofaccessanddelivery.Wepresentvariousconfigurationsofthesystemanddescribetheiruseinthecollaboration.

  • 标签: SAM 数据处理系统 D0实验
  • 简介:In2010,theBESCollaboration[1]foundaclearenhancementintheK0K0massdistributionintheJ=ψ!ηK0K0decay.SuchanenhancementisusuallyasignatureofanL=0resonancearoundthreshold,whichinthiscasewouldcorrespondstoanh1statewithquantumnumbersIG(JPC)=0??(1+??).Thish1statewaspredictedbytheChiralUnitarytheoryintheKKinteraction.Becauseoftheconversationlaw,thisstatecanonlydecaytoK0K0channel,andcanbestudiedefficientlyintheJ=ψ!ηK0K0decay.

  • 标签: SIGNATURE SIGNATURE QUANTUM CLEAR can BES
  • 简介:WereportonthefirstoperationsofthereconstructionfarmsfortheD0experiment.Datawerereadfromataperobotto50PC'srunningLinux,processed,spooledtoacentraldiskbufferformergingandthenwrittenbacktothetaperobot.Thefarmsarebeingusedsuccessfullytoreconstructthedataasitcomesin.Transferrateswelloverthe12.5MB/secneededforfulldatarateshavebeenachieved.

  • 标签: D0实验 探测器 软件开发
  • 简介:Oneofthekeycomponentsofanygridarchitectureismanagingcomputeandstorageresourcesandoptimizingtheirutilization.SAMhasimplementedfeaturesthatallowittoexercisea"fairshare"and"prioritized"policyamongmanygroupsofusers.Thegoalsareasfollows:1)implementthexperimentspoliciesforresourceusagebyresearchgroupandbydataaccessmode,and2)optimizetheresourceusagetomaximizetheoverallthroughputdefinedintermsofrealdataprocessingactivity,AtthelowestlevelofSAMarchitecture,calledthestation,theSAMsystemintegratesthedatadeliveryandcachemanagementwiththejobcontrolandschedulingofthebatchsystem.Atthesite-level,forexampleatFermilab,requestsfordatafromon-sitestationsaremanagedtooptimizeMassStorageSystemresourcesandnetworkthroughput,Managementofresourcesatavariousgeographiclevelsarediscussed.

  • 标签: 广域网 数据管理 数据存储 D0数据网格
  • 简介:IGUANA(InteractiveGraphicsforUserANAlysis)isaC++toolkitfordevelopinggraphicaluserinterfacesandhighperformance2-Dand3-Dgraphicsapplications,suchasdatabrowsersanddetectorandeventvisualisationprograms.TheIGUANAstrategyistousefreelyavailablesoftware(e.g.Qt,SoQt,OpenInventor,OpenGL,HEPVis)andpackageandextendittoprovideageneral-purposeandexperiment-independenttoolkit.WedescribetheevaluationandchoicesofpubliclyavailableGUI/graphicssoftwareandtheadditionalfunctionalitycurrentlyprovidedbyIGUANA.WedemonstratetheuseofIGUANAwithseveralapplicationsbuiltforCMSandD0.

  • 标签: 计算机图形学 交互图形 CMS DO CMS
  • 简介:Aswellknown,iftheHiggsbosonwerenotobservedatLHC,thetechnicolormodelwouldbethemostfavorablecandidateresponsibleforthesymmetrybreaking.Toovercomesomedefectsinthepreviousmodel,someextendedversionshavebeenproposed.IntheTC2modeltypicalsignatureisexistenceofheavyH_(TC)andtechnipionП.Adirectproofofvalidityofthemodelistoproducethemataccelerator.Thuswestudytheproductionratesofe~+e~-→H_(TC)П~0ande~+e~-→П~+П~-atILCinthetopcolor-assistedtechnicolor(TC2)model.Infact,thereisafloodofmodelsbelongingtonewphysics,whichcanresultinproductswithcharacteristicssimilartoH_(TC)+ПoftheTC2model.ThereforetodistinguishthismodelfromothersonemayneedtoinvestigatesomedetailsbycalculatingthecrosssectiontoNLO.WeindeedfindthattheNLOcorrectionsaresignificant,namelytheratioδ2≡(σ_(NLO)-σ_(LO))/σ_(LO)ine~+e~-→H_(TC)П~0exceeds100%withinaplausibleparameterspace.

  • 标签: TECHNICOLOR模型 非线性光学 审判 国际 矫正 希格斯玻色子
  • 简介:ThespectrumoftheΣ(1193)excitedstates,Σ,withisospinI=1andstrangenessS=??1isoneofthemostimportantissuesinhadronicphysics.TheΣresonancesaremostlyproducedandstudiedinK-inducedreactions.ManyΣresonancesarenowcatalogedbytheParticleDataGroup[1].However,ourknowledgeoftheseresonancesisstillverypoor.Intheenergyregionbelow2GeV,onlyafewofthemarewellestablished,suchastheΣ(1385)ofspin-parityJP=3=2+,Σ(1670)ofJp=3=2??andΣ(1775)ofJp=5=2??.Theothersarenotwellestablishedandsomeofthemareevenoflargeuncertaintiesontheirexistence.Thus,thestudyoftheΣresonancewiththeavailableexperimentaldataisnecessary.

  • 标签: EXPERIMENTAL Π now OUR is
  • 简介:Thetop-pairproductioninassociationwithaZ~0-bosonataphoton-photoncolliderisanimportantprocessinprobingthecouplingbetweentop-quarksandvectorbosonanddiscoveringthesignatureofpossiblenewphysics.WedescribetheimpactofthecompletesupersymmetricQCD(SQCD)next-to-leadingorder(NLO)radiativecorrectionsonthisprocessatapolarizedorunpolarizedphotoncollider,andmakeacomparisonbetweentheeffectsoftheSQCDandthestandardmodel(SM)QCD.Weinvestigatethedependenceofthelowest-order(LO)andQCDNLOcorrectedcrosssectionsinboththeSMandminimalsupersymmetricstandardmodel(MSSM)oncollidingenergys~(1/2)indifferentpolarizedphotoncollisionmodes.TheLO,SMNLO,andSQCDNLOcorrecteddistributionsoftheinvariantmassoftt-pairandthetransversemomentaoffinalZ~0-bosonarepresented.OurnumericalresultsshowthatthepureSQCDeffectsinγγ→ttZ~0processcanbemoresignificantinthe++polarizedphotoncollisionmodethaninothercollisionmodes,andtherelativeSQCDradiativecorrectioninunpolarizedphotoncollisionmodevariesfrom32.09%to-1.89%whens~(1/2)goesupfrom500GeVto1.5TeV.

  • 标签: 量子色动力学 光子对撞机 矢量玻色子 超对称 非线性光学 碰撞模式
  • 简介:Zr1-xTixCo(x=0,0.1,0.2,0.3)alloyswerepreparedbyarc-meltingmethodandtheeffectofTisubstitutiononhydrogenstoragepropertieswasstudiedsystematically.Hydrogendesorptionpressure-composition-temperature(PCT)measurementswerecarriedoutusingSievert’stypevolumetricapparatusforZrCo(at473K,573Kand673K)andZr1-xTixCoalloys(at673K),respectively.ProductsafterdehydrogenationwerecharacterizedbyX-raydiffraction(XRD).Inaddition,thekineticsofZr1-xTixCohydridewasinvestigatedat473Kand673K,respectively,underhydrogenpressureof5MPa.ResultsshowedthatTisubstitutionforZrdidnotchangethecrystalstructureofZrCophase.Withtheincreaseoftemperaturefrom473Kto673K,theextentofdisproportionationforZrCoalloyincreased.WithTicontentincreasingat673K,thedesorptionequilibriumpressureofZr1-xTixCo-H2systemselevatedandthedisproportionationreactionofZr1-xTixCoalloyswasinhibitedeffectively.TisubstitutiondecreasedthekineticsrateandtheeffectivehydrogenstoragecapacityofZr1-xTixCoalloysslightly.Generallyspeaking,itwasfoundthatZr0.8Ti0.2Coalloyhadbetteranti-disproportionationpropertywithlessdecreaseofeffectivehydrogenstoragecapacitywhichwasbeneficialtotritiumapplicationintheInternationalThermonuclearExperimentalReactor(ITER).

  • 标签: ZrCo-based ALLOYS TI substitution hydrogen storage
  • 简介:我们证明认识到量重叠是可能的切换上并且离开在一个单个量点的强壮的轻事的相互作用--半导体microcavity系统。如此的重叠启用有条件的动力学完成的违反直觉的量的观察。状况是可能的象emitter光一样的洞光子显示指数的腐烂的地方,但是他们的联合察觉概率展出真空Rabi摆动。显著地,这些量关联也是在nonequilibrium的现在如此的协调地驾驶的消散的量系统的稳定的州的系列。

  • 标签:
  • 简介:WeinvestigateindetailtheeffectsofR-parityleptonnumberviolationonthedecay~↑b1→b~↑x1^0intheR-parityviolatingminimalsupersymmetricstandardmodel(Rp-MSSM)underthepresentexperimentalconstraintsonRpparameters.Inournumericalcalculationsweconsidertwocasesofinputparametersofthesquarkandsleptonsectors,MsquarkMslepton,forcomparison.TheresultsshowthattherelativeR-parityviolatingcorrectionisnotverysensitivetothemassofthelightestneutralino-0↑x1andthedegenerateR-parityviolatingcouplingparameterλ2′,butstronglydependsonMsquark,Mslepton,tanβandthedegenerateR-parityviolatingcouplingparameterλ1′.Therelativecorrectionisabout-4~3%andcanexceed-6%insomeregionofparameterspace.Therefore,preciseexperimentanalysesonthedecay~↑b1→b~↑x1^0mayprovideaprobeoftheR-parityviolation.

  • 标签: R-奇偶效应 最小超不对称模型 质子 稳定性 重子数
  • 简介:采用燃烧法合成了La1.6(MoO_4)_3:Eu_0.4^3+纳米晶末,研究了其声子一掺杂-晶格相互作用和发光性质。x射线粉末衍射(XRD)分析表明,在500~900℃退火后,La1.6(MoO_4)_3:Eu_0.4^3+样品为单一晶相。对样品进行了光致发光(PL)测量,激发Mo^6+-O^2-电荷迁移带,观察到Eu^3+的系列发光,表明Mo^6+-O^2-带和Eu^3+间存在能量传递,中心波长分别在λ1=469nm和λ2=426nm处的两个one-phonon边带,相应的声子能量分别为767和1202cm^-1,分别对应于Mo=0和Mo-0-Mo伸缩振动。同时,计算了两个局域模电子一声子耦合强度的黄昆因子分别为S1=0.055和S2=0.037,为揭示其三价离子高传导特性及其负热膨胀物理特性提供了实验基础。

  • 标签: 发光特性 燃烧法 La1.6(MoO_4)_3:Eu_0.4^3+纳米晶 局域模 one-phonon边带