简介:ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].
简介:TheprogressofresearchgoingoninGroupofEnergyMaterials(GEM),MaterialResearchCenter,in2014isinthefollowingthreeaspects.1.FacilitydevelopmentInordertopushforwardourstudyonfusionreactormaterials,weupgradedtheirradiationterminal(128#)ofthesectorfocusedcyclotron(SFC)atHIRFL,bydevelopinganewspecimenstagespecificforirradiationwithlow-fluencescatteredions.Sofartheterminaliscapableofirradiationtobothverylowfluences(106ions/cm2)andveryhighfluences(typically1016ions/cm2)forvariousmaterials.SpecimentemperaturecanbereadilycontrolledusingtheL-N2coolingstageorthethehigh-Tstage(upto600oC).Ourrecentinvestigationwithtransmissionelectronmicroscopy(TEM)ofthedefectsproducedbyhigh-energyNeionsinsteelspecimensprovidesaclearevidencethatdefectswereproduceduniformlyalongthedepthinthespecimen,indicatingthattheenergydegraderoftheterminalworkseffectivelytodispersetheionenergyinawiderange.AphotooftheterminaltogetherwithaSRIMestimateofdepthprofilesofdamageinan8%Crreducedactivationferritic/martensiticsteel(RAFMS)isshowninFig.1.
简介:Theresearchacceleratorsaregrowinginenergyandpowerwhichinducesanincreaseoftheprojectcosts(Fig.1).TheRFcavitiesandpowersupplymainlycontributethecostofthesuperconductinglinac,whichisacompetitivetechnologyforhighpowermachine.AcodewithoptimizationalgorithmisdevelopedtooptimizethebetavalueofSCcavityfamilyandtransitionenergytoincreasetheTTFvalueofthewholelinac.
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简介:SpokecavitieshavebeendevelopedandhaveapparentadvantagesforhighcurrentprotonacceleratorbasedonFig.1(coloronline)Theelectromagneticfielddistribution.superconductivityatlowandmediumenergyregion.Astheresearchandthetechnicalreserve,InstituteofModernPhysics(IMP)hasstartedtheR&Dprogramofadoublespokecavity(operatingfrequency325MHz,0=0.52),withintheframeworkofChinaAcceleratorDrivenSystem(C-ADS)project.TheRFdesignandmechanicalstructuredesignhavebeenfinished,andtwoprototypecavitiesweremanufacturedinHarbin.
简介:ThegatedielectricthicknessdecreasesdramaticallywiththecontinuousscalingofMOSdevices,whichhasseriousconsequencesontheleakagecurrentandthepowerconsumptionoftheSiO2-basedMOSdevices.Hafniumdioxide(HfO2),asakindofhigh-kmaterial,arerecognizedasalternativestoSiO2forfutureadvancedgatedevicesandspaceapplications[1].Radiation-inducedeffectsonconventionalSiO2dielectricshavebeeninvestigated.Now,anenormousamountofeffortwasrequiredtoadaptthenewhigh-ksystemsforradiationhardapplication.
简介:In2014,researchersinthehighenergynuclearphysicsgroupatIMPhavecarriedouttheirresearchworkonhadronphysics.Severalinterestingresultswereobtainedandpublished.Themesonandbaryonexcitedstateshavebeenstudiedinalargenumberofformationandproductionexperiments.Thestudyofmesonresonancesandthesearchforglueballs,hybrids,andmultiquarkstateshaveremainedanactiveandinterestingfieldofhadronphysics,whileforbaryons,theinvestigationofthebaryonspectrumandthebaryoncouplingsfromexperimentaldataarealsothemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.StudyinghadronresonancesiscrucialtounderstanddeeplytheQCDtheoryatnonperturbativeenergyregion,anditisalsoimportantfornuclearphysicsandparticlephysics.