the physics case nuclear structure外语英文电子书

《the physics case nuclear structure外语英文电子书》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、CHAPTER1THEPHYSICSCASE1.1NuclearPhysicsTheatomicnucleusistheparadigmoffinite,many-bodysystems,wherequantalsizeeffectsplayacentralrole.Sofar,ourknowledgeonnuclearstructurehasbeenmostlygainedbystudyingnucleinearthevalleyofbetastabilityorontheneutron-deficientside,withrespecttothevariablesof

2、excitationenergyandspin.Newcombinationsofprotonandneutronnumbers,i.e.theisospindegreeoffreedom,areexpectedtoprovidenewinformationonthenuclearforces.Neweffectswillbediscussedinthefollowingasamotivationforthedesignandconstructionofafacilitydevotedtoaccelerationandexperimentswithneutron-rich

3、radioactivenuclei.Themaingoaloftheproposedfacilityistoprovideanacceleratorsystemtoperformforefrontresearchinnuclearphysicsbystudyingnucleifarfromstability.Initsfirstconfiguration,theSPESprojectisconcentratingontheproductionofneutron-richradioactivenucleiwithmassintherange80-160.However,th

4、isacceleratorsystemwillallowtoproducealsolighterionsorprotonrichnucleibyadding,inasecondphaseoftheproject,fewelementstotheacceleratorcomplex.Theemphasistoneutron-richisotopesisjustifiedbythefactthatthisvastterritoryhasbeenlittleexplored,ifoneexceptssomedecayandin-beamspectroscopyfollowing

5、fission.Therefore,reactionsininversekinematicswillallowanewclassofdatatobeobtained.ThefinalenergyoftheradioactivebeamsontargetwillrangefromfewMeV/utoapproximately20MeV/u.ThisenergyallowstoovercometheCoulombrepulsionbetweentheradioactivebeamandthetargetnucleiinmostsystemsandopensupnewpossi

6、bilitiesforexperimentalstudiesofneutron-richnucleiemployingdifferentreactionmechanismssuchasCoulombexcitation,inelasticscattering,single-andmultiple-nucleontransfer,fusionreactions,etc.Suchreactionsnotonlyprovideinvaluablenuclearstructureinformationbuttheyalsoallowtoreachnucleievenfurther

7、awayfromthestabilityline.Beamsofneutron-richnucleiofferbetterchancestosynthesizeheavyelementsbecausethefusedsystemwillbelessneutrondeficient,thereforeclosertothevalleyofstabilityandwithbetterchancestosurvive.Itmustbementionedtoothattheveryhighintensityofthedriveracc