摘要
把束缚核子内海夸克从物理上分为两部分：一部分是伴随价夸克受核束缚效应影响的云海夸克；另一部分是能摆脱核子的禁闭而逃逸到核环境中的背景海夸克．首先，给出了核束缚效应对核内束缚核子中价夸克、云海夸克及相应胶子的纵向动量几率分布函数的最低级修正形式；借助核动量守恒条件定出了背景海夸克及相应胶子的动量几率分布函数．然后，根据部分子内禀横向动量分布与纵向动量分布间的制约关系及我们关于核环境中部分子间相互演化的观点，建立了决定平均核结构函数的束缚核子内部分子动量几率分布所满足的自洽积分方程组，并进行了迭代数值求解．最后，我们将所得的束缚核子内部分子动量几率分布应用到解释ＥＭＣ效应及预言核Ｄｒｅｌ－Ｙａｎ反应截面，在没有引进任何可调参数的情况下。
In this paper,we separate sea quarks in bound nucleon into two parts:one part,which is affected by the nuclear binding effect together with valence quark, is called cloud sea quark;another part,which can get rid of the confinment of nucleons and go into the nuclear medium, is called background sea quark.Firstly,we give the lowest order modification of the nuclear binding effect to longitudinal momentum distributions of valence quarks,cloud sea quarks and corresponding gluons and determine the momentum distributions of background sea quarks and corresponding gluons by using the condition of momentum conservation.And then we set up the self-consistent integral equations for the parton distributions in bound nucleons that determine the average nuclear structure function according to the constraint interrelationship between the intrinsic tansverse momentum and longitudinal momentum distributions and our previous view point of parton evolution in the nuclear mediun and obtain the numerical solution of these equtions in the successive substitution method.Finally,the obtained parton distributions in bound nucleons are applied to explain the EMC effect and expect the nuclear Drell-Yan ratio without any free parameter,the result is satisfactory.
出处
《南京师大学报（自然科学版）》
CAS
CSCD
1996年第2期29-35,共7页
Journal of Nanjing Normal University(Natural Science Edition)
基金
国家自然科学基金
江苏省自然科学基金
