强子衰变对高能反应末态超子极化的影响  

Decay Contributions to Hyperon Polarization in High Energy Reactions

作　　者：李媛[1] 邵凤兰[2] 

机构地区：[1]青岛大学师范学院物理系 [2]曲阜师范大学物理系,曲阜273165

出　　处：《高能物理与核物理》2007年第9期810-814,共5页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金(10475049);曲阜师范大学科研启动基金资助~~

摘　　要：在分析不同情形超子衰变的基础上,给出超子衰变对超子产生率和末态超子极化的贡献的一般计算公式.用Monte-Carlo数值计算研究强子衰变对高能反应末态超子极化的影响,结果发现,强子衰变对A超子的贡献很大这一结论具有普遍性,与模型无关;不同模型给出的单极化pp碰撞产生的大横动量A超子极化的差别,很可能相当大一部分来源于强子衰变.考虑到衰变对极化贡献的计算中有较大不确定性,检验不同模型,最好看∑~±,Ξ~0,Ξ^-的极化.By analyzing different hyperon decay processes, we derive the general formula for the decay contributions of heavier hyperons to hyperon production rates and final-state hyperon polarizations. Using a Monte-Carlo event generator, we study the decay contributions of hadrons to the final state hyperon polarizations in high energy reactions. The calculated results show that the decay contributions to the A polarization from other hyperons are very large and this result is universal and model independent. The polarization difference of A with high p⊥ in the singly polarized pp collision among different models may mainly come from the decay contributions of hadrons. Considering the uncertainties of such calculations, the polarizations of ∑^±,Ξ^0,Ξ^- would be better quantities for testing models.

关 键 词：超子极化 强子衰变 极化碎裂函数 

分 类 号：O571.32[理学—粒子物理与原子核物理]