简介：

简介：In2014,theresearchersofTheoreticalPhysicsGroupatIMPhavecarriedouttheirresearchworkonnuclearphysics,heavyionphysicsandhadronphysics.Someimportantresultshavebeenobtained.Thethree-bodyforce(TBF)effectontheoff-shellbehavioroftheneutronandprotonmassoperatorsinasymmetricuclearmatterhasbeeninvestigatedwithintheframeworkoftheextendedBrueckner-Hartree-Fockapproach[1].Athighdensitieswellabovethenormalnuclearmatterdensity,theTBFisshowntoaffectsignificantlytheoff-shellehaviorofboththeprotonandneutronmassoperators.Thedensitydependenceofsymmetryenergyaroundtheuclearsaturationdensityhasbeenstudied[2].Anewapproachhasbeenproposedandappliedtodeterminetheymmetryenergycoefficientofheavynucleibasedontheavailableexperimentalnuclearmassesofheavynuclei.Theobtainedresultisadoptedtoanalyzethedensitydependenceofsymmetryenergyofnuclearmatteraroundtheaturationdensity.TheslopeparameteratthesaturationdensityisdeterminedtobeL=(50.515.5)MeV.

简介：In2010,theBESCollaboration[1]foundaclearenhancementintheK0K0massdistributionintheJ=ψ!ηK0K0decay.SuchanenhancementisusuallyasignatureofanL=0resonancearoundthreshold,whichinthiscasewouldcorrespondstoanh1statewithquantumnumbersIG(JPC)=0??(1+??).Thish1statewaspredictedbytheChiralUnitarytheoryintheKKinteraction.Becauseoftheconversationlaw,thisstatecanonlydecaytoK0K0channel,andcanbestudiedefficientlyintheJ=ψ!ηK0K0decay.

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.

简介：针对GM（1,1）模型的适用范围是近指数情况,提出了将优化灰导数与利用原始序列模拟的相对误差平方和最小估计预测系数c相结合的方法,从而得到一种简化计算的新GM（1,1）优化模型,该模型的预测公式x（0）（k）=ce-ak在形式上比较简洁,并且经严格指数序列从理论上验证了参数a具有白化指数律重合性,预测系数c具有白化系数重合性.

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简介：DarkMatterParticleExplorer(DAMPE)isapowerfulspacetelescopeforhighenergycosmicraysdetectionsuchas-ray,electronandheavyions.ThemainmotivationofDAMPEistofindtheevidenceofdarkmatterexistence,andthesatelliteisscheduledforlaunchingbeforetheendof2015.ThePlasticScintillatorDetector(PSD),whichisoneofthekeycomponentsoftheDAMPEsystem,hastwomajorfunctionalities:distinguishphotonsfromchargedparticlesbyanti-coincidenceandmeasurethechargeofheavyions.ThePSDisdesignedandfabricatedbytheinstituteofmodernphysics,CAS.Itconsistsof82plasticscintillatorstrips,eachofwhichisreadoutbyPMTatbothends,andadouble-dynodereadoutschemeforPMTisutilizedinordertocoverthelargedynamicrange(fromHtoCa).

简介：Accordingtothenaiveconstituentquarkmodel,the?mesonisbelievedtobeanalmostpuressstate,whilethereareonlyupanddownquarks(antiquarks)inthenucleon(antinucleon).Thusthepp!??reaction,withitsdisconnectedquarklines,shouldbesuppressedaccordingtotheOkubo-Zeig-Iizuka(OZI)rule.However,eventheOZIruleisstrictlyenforcedbynature,theppreactioncanstillproceedthroughthenon-strangequarkcomponentofthe?meson,becauseoftheslightdiscrepancyfromtheidealmixingofthevectormesonsingletandoctet[1].Withthissmalldiscrepancy,onecandetermineanupperlimitforthetotalcrosssectionofpp!??reactionbycomparisontothetotalcrosssectionoftherelatedpp!ωωreaction.Thisyieldsacrosssectionforpp!??attheorderof10nb.However,theexperimentalresultshowedthatthecrosssectionat1.2GeVincidentanti-protonmomentum,=2.860.46μb,istwoordersofmagnitudelargerthantheestimatedvalue.Hence,thepp!??reactionhasattractedmuchattentionbecauseofthelargeviolationoftheOZIrule.

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简介：AgraphissaidtobeK1,4-freeifitdoesnotcontainaninducedsubgraphisomorphictoK1,4.Letkbeanintegerwithk≥2.WeprovethatifGisaK1,4-freegraphoforderatleast11k-10withminimumdegreeatleastfour,thenGcontainskvertex-disjointcopiesofK1+(K1∪K2).

简介：Thesymmetryenergy,whichgovernsmanyphysicalphenomenafromthestructureofexoticnucleitoastrophysicalprocesses,hasmanyramificationsinbothnuclearphysicsandastrophysics.Althoughnuclearsymmetryenergyanditsslopeatthenormaldensityofnuclearmatterhavebeenroughlypinneddown,recentinterpretationsofFOPIandFOPI-LANDdatabydifferenttransportmodelsleadtodivergentconclusionsonthedensity-dependentsymmetryenergyatsupradensities.

简介：The(2+1)-dimensionalBKPequationintheHirotabilinearformisstudiedduringthiswork.WronskianandGrammiantechniquesareappliedtotheconstructionofWronskianandGrammiansolutionsofthisequation,respectively.ItisshownthatthesesolutionscanbeexpressedasnotonlyPfaffiansbutalsoWronskiansandGrammians.

简介：上海市社会总抚养比受到诸多因素的影响,导致数据波动性较大,单纯地采用灰色预测模型无法更加准确地进行预测,因此文章提出了基于最小二乘法的改进GM（1,1）模型.首先文章介绍了普通GM（1,1）模型的建立方法与步骤;接着通过采用最小二乘法的原理弱化波动较大的数据,加强其规律性从而建立新的GM（1,1）模型;最后结合2007-2011年上海市社会总抚养比数据建立新的预测模型,并用2012年数据对模型进行验证合格,可以用来预测未来几年上海市社会总抚养比,便于该市对未来经济的发展宏观调控.结果表明该预测方法是合理可行的,为其他相关预测提供了理论依据.

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简介：Morelocalizedenergydepositionisabletobeproducedinantiproton-nucleuscollisionsincomparisonwithheavy-ioncollisionsduetoannihilationreactions.Searchingforthecoldquark-gluonplasma(QGP)withantiprotonbeamshasbeenconsideredasahottopicbothinexperimentsandinthereticalcalculationsoverthepastseveraldecades.Strangenessproductionandhypernucleusformationinantiproton-inducednuclearreactionsareimportanceinexploringthehyperon(antihyperon)-nucleon(HN)potentialandtheantinucleon-nucleoninteraction,whichhavebeenhottopicsintheforthcomingexperimentsatPANDAinGermany.

简介：In2014,researchersinthehighenergynuclearphysicsgroupatIMPhavecarriedouttheirresearchworkonhadronphysics.Severalinterestingresultswereobtainedandpublished.Themesonandbaryonexcitedstateshavebeenstudiedinalargenumberofformationandproductionexperiments.Thestudyofmesonresonancesandthesearchforglueballs,hybrids,andmultiquarkstateshaveremainedanactiveandinterestingfieldofhadronphysics,whileforbaryons,theinvestigationofthebaryonspectrumandthebaryoncouplingsfromexperimentaldataarealsothemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.StudyinghadronresonancesiscrucialtounderstanddeeplytheQCDtheoryatnonperturbativeenergyregion,anditisalsoimportantfornuclearphysicsandparticlephysics.

简介：Thestudyofnucleonresonanceisanimportanttopicinhadronphysics.Themostimportantwaytostudythenucleonresonancesisthecollisionofthephotonandnucleon.Uptonow,theknowledgeaboutthenucleonresonancesaround2GeVisstillscarce.Recently,theCLASCollaborationatJeffersonNationalAcceleratorFacilityreleasedtheirexclusivephotoproductioncrosssectionsfortheΛ(1520),Σ0(1385)andΛ(1405)forenergiesfromnearthresholduptoacenterofmassenergyWof2.85GeVwithlargerangeoftheKproductionangle[1].SincethethresholdforthephotoproductionofΛ(1520)isabout2.01GeV,thenewexperimentaldatawithhighprecisionreleasedbytheCLASCollaborationprovideanopportunitytostudythenucleonresonancesabove2GeV.

简介：Thesymmetryenergywhichcharacterizestheisospindependenceoftheequationofstateofasymmetricnuclearmatter,playsacrucialroleinunderstandingavarietyofissuesinnuclearphysicsandastrophysics,suchasheavyioncollisions,exoticnuclei,stabilityofsuperheavynuclei,fusioncrosssections,thestructures,compositionandcoolingofneutronstars[1??5].Muchtheoreticalandexperimentalefforthasbeenmadetoconstrainthedensitydependenceofsymmetryenergy.Uptonow,wehavegotsomebasicknowledgeaboutthesymmetryenergyatlowdensities,whileathighdensitiesweevendonotknowitsvariationtendencyasafunctionofdensity.Theproblemremainsunsolvedduetothedifficultyofnucleon-nucleoninteractionsandmany-bodyproblems.

简介：Nucleon-nucleon(NN)correlationsandtheirisospindependenceinasymmetricnuclearmatterareofgreatnterestsincetheyarecloselyrelatedtothestructureofneutron-richnuclei[1],particleproductioninheavy-ionollisions[2],andneutron-starphysics[3].Themany-bodycorrelationsamongnucleonscanbedirectlyreflectedintheneutronandprotonspectralfunctions[4],andthelattermayplayanimportantroleinunderstandingthenatureftheNNcorrelations,especiallytheshort-rangeandtensorcorrelationsinasymmetricnuclearmatter.

简介：BystudyingthespectralpropertiesoftheunderlyingoperatorcorrespondingtotheM/G/1queueingmodelwithoptionalsecondserviceweobtainthatthetime-dependentsolutionofthemodelstronglyconvergestoitssteady-statesolution.Wealsoshowthatthetime-dependentqueueingsizeatthedeparturepointconvergestothecorrespondingsteadystatequeueingsizeatthedeparturepoint.