πp碰撞中η_c与γ的协同硬衍射产生  

η_c and γ Associated Production in Hard Diffractive πp Collision

作　　者：阎占元[1] 张健[1] 

机构地区：[1]华北电力大学数理学院,河北保定071003

出　　处：《河北师范大学学报（自然科学版）》2013年第5期484-487,共4页Journal of Hebei Normal University：Natural Science

基　　金：国家自然科学基金(11075044)

摘　　要：利用硬衍射产生过程的因子化方案与重夸克偶素的色八重态产生机制,计算了π介子与质子的衍射过程中ηc与γ协同产生的微分截面与总截面,在NRQCD理论框架下,ηc的产生是一个纯色八重态过程,在大pT区域,ηc+γ产生的贡献主要来自于|c(1S0(8))〉,而它的长程矩阵元的数值更为可靠,进而计算得到ηc的产生结果较为可靠.计算结果显示,微分截面dσ/d y随着y的增加而下降.用3套Pomeron中胶子的分布函数计算得到的总截面相差明显.The differential cross section and total cross section of associated ~？c and y production in hard diffractive πp collision are calculated based on ingelman-schlein model and heavy quarkonium color-octet production mechanism. In the framework of NRQCD factorization formalism,the production of ηc is a pure color-octet process,the main contribution comes from ｜cc （1S0^（8）） state, whose long distance matrix elements are more reliable. The result shows a decline of dσ/dy with the increasein y. An remarkable difference for total cross section a are obtained by three sets of gluon distribution functions in Pomeron. Further measurement of the process in experiments will test the assumption of hard diffractive factorization in hadron-hadron collisions and gluon distribution function of Pomeron.

关 键 词：衍射过程 色八重态 POMERON 

分 类 号：O571.24[理学—粒子物理与原子核物理]