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1、蘭州大學(xué)博士研究生學(xué)位論文密度分布模型計算所得結(jié)果均小于氘密度分布為常數(shù)時的計算結(jié)果。研究發(fā)現(xiàn)在Yb，Pd材料中D(d，p)T反應(yīng)具有溫度效應(yīng)，即在相同彈核能量條件下，質(zhì)子的產(chǎn)額隨溫度升高而降低。這項工作首次研究了氘密度深度分布對屏蔽勢能推導(dǎo)帶來的影響，提出有關(guān)氘分布模型并加以驗證，運用模型重新計算了屏蔽勢能。盡管如此，實驗數(shù)據(jù)處理中還有不確定性：一是氘在相關(guān)介質(zhì)中的阻止本領(lǐng)，在如此低的能區(qū)還沒有阻止本領(lǐng)的實驗數(shù)據(jù)，只能采用理論編評的結(jié)果(用SRIM計算)：二是反應(yīng)截面也是采用理論推導(dǎo)結(jié)果，需要有更高精度的計算；三是文中所提出的氘靶核密度分布模型較為粗糙，會給計算結(jié)果帶來一定的誤
2、差，需要進一步完善。關(guān)鍵詞：電子屏蔽效應(yīng)含氘金屬靶密度深度分布AbstractAlastingtopicinnuclearastrophysicsisthescreeningofthenuclearCoulombpotentialduetotheatomicelectronsinlaboratorynuclearphysicsexperimentswhichenhancestheexperimentalreactioncross-sectionsatlowenergiesrelativetothebarenucleus．Thecrosssectionsofnuclearfusio
3、nreaction盯(E)inenergyregionfarbelowtheCoulombbarrierisroughlyrepresentedbytheGamowfac-tor，anddropsexponentiallywithdecreasingprojectileenergy,whicharehardtobemeasuredaccuratelyandareextrapolatedfromthedataathigherenergiescustomarily．TheCoulombpotentialofthetargetnucleusandprojectiletheoret—ic
4、allycalculatedfrombarenucleistates．However，thetargetnucleistudiedinlaboratoryareusuallyintheformofatomsormolecules，SOthattheCoulombbarrieriseffectivelyreducedbothinheightandradialextension．Asaresult，thecorrespondingcrosssectionsarehigherthanwouldbethecaseforbarenuclei．Theenhancedcrosssectiona
5、s(E)isexpressedasas(E)=ab(E+玩)withanelectronscreeningpotential玩，andab(E)isthecrosssectionforbarenucleus．TheD(d，p)Treactionsindifferentmaterialsinsub-lowenergyregionhavebeenstudied．Thoughanalysismethodsforthe鞏ofD(d，p)Treactioninmetalenvironmentweredifferent，theywereallbasedonanassumptionofasta
6、bleandhomogeneousdeuterondensitydistribution．However，thedeuteronatomissmallerthananymetalatomsanditsutmosthi【ghmobilitynlakestheassump-tiondoubtful．Therefore，onecansupposeneitherastablenorahomogeneousdeuterondensitydistributionwhichisrequiredbythestandardanalysismethod．Soaroughmodelofdeuteron
7、sdensitydistributionisintroduced．TheexperimentwasperformedattheLaboratoryofNuclearScience，To-hokuUniversity．ThedeuteratedthicktargetsusedinthisworkareBe，A1，蘭州大學(xué)博士研究生學(xué)位論文Dy,YbandZrmetal，respectively．Theprojectileenergyrangeis5keV--。10keV(CMS)，
