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：为实现对大型复杂结构在冲击载荷下的高效率数值模拟，采用弹塑性流体力学模型，设计了区域分解的显式动力学有限元并行算法，并基于面向对象的、具有并行与网格自适应功能的有限元软件包AFEPack，方便地解决了非结构网格的自动区域划分、内边界上的数据通信和动态负载平衡等关键技术问题，并开发了三维拉格朗日动力学有限元程序。通过算例验证，计算结果合理，与LS-DYNA3D计算结果符合较好，表明关键算法及程序正确，具有较高的并行效率。

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

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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：Weprovideanewclassofinteriorsolutionofa(2+1)-dimensionalanisotropicstarinFinchandSkeaspacetimecorrespondingtotheBTZblackhole.WedevelopthemodelbyconsideringtheMITbagmodelEOSandaparticularansatzforthemetricfunctiongrrproposedbyFinchandSkea[M.R.FinchandJ.E.F.Skea,Class.Quantum.Grav.6(1989)467].Ourmodelisfreefromcentralsingularityandsatisfiesallthephysicalrequirementsfortheacceptabilityofthemodel.

简介：Thedeuteronisalooselyboundstateoftwonucleons.Itisnaturaltoexpectotherboundstatescomposedoftwohadrons,thatis,hadronicmolecularstates[1].AftertheobservationbytheBelleCollaboration,theX(3872)wasrelatedtoalooselyboundstateofDˉDimmediatelyduetothefactthatitsmassisneartheDˉDthreshold.Recently,theBelleCollaborationannouncedtwochargedbottomonium-likestructuresZb(10610)andZb(10650)neartheBˉBandBˉBthresholds[2].TheanalysisoftheangulardistributionindicatedbothZb(10610)andZb(10650)favorIG(JP)=1+(1+).AstructureZc(3900)closetotheDˉDthresholdwasalsoobservedbytheBESIIIcollaborationinthedecayofY(4260),Y(4260)!+??J=[3].

简介：Thebaryonspectrumandthebaryoncouplingsaretwoofthemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.Bothontheexperimentalandtheoreticalsides,thenucleonexcitedstatesbelow2.0GeVhavebeenextensivelystudied[1].However,thecurrentinformationforthepropertiesofstatesaroundorabove2.0GeVisscarce.Ontheotherhand,inthisenergyregion,manytheoreticalapproacheshavepredictedmissingNstates,whichhavenotbeensofarobserved.Hence,thestudyofthepossibleroleplayedbythe2.0GeVregionnucleonresonancesintheavailableaccuratedataistimelyandcouldshedlightintothecomplicateddynamicsthatgovernsthehighexcitednucleonspectrum.

简介：π-/π+ratiowasfoundtobeasensitiveprobetothehigh-densitybehaviorofthesymmetryenergybyusingseveraltransportmodels.However,asshowninFig.1,atbeamenergiesbelowthepionproductionthreshold,theeffectsofin-mediumnucleon-nucleonscatteringcrosssection(whichisstillcontroversial)stronglyaffectthevalueofπ??/π+ratio[1].Itisthusnecessarytodoacomparativestudyoftheeffectsofthein-mediumNNcrosssectionandtheeffectsofthesymmetryenergyonpionproductioninheavy-ioncollisionsatlowerbeamenergies.

简介：Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].