BESIII π^+π^-形状因子测量以及π^+π^-π~0展望（英文）  

BESIII π^+π^- form factor measurement and perspective of π^+π^-π~0

作　　者：无 王亚乾 

机构地区：[1]besiii合作组 [2]美因茨大学,德国美因茨55128

出　　处：《中国科学技术大学学报》2016年第4期301-307,共7页JUSTC

基　　金：Supported by German Research Foundation DFG under Collaborative Research Center(CRC-1044)

摘　　要：利用BESIII在3.773GeV获取的2.93fb-1数据,测量了600~900 MeV/c^2区间e^+e^-→π^+π^-的截面.分析主要基于初态辐射的方法,总的系统误差控制在0.9%.通过计算得到的形状因子|F_π|~2与其他两个实验做了比较.两π过程对缪子反常磁矩的贡献为a_μ^(ππ,LO)(600~900 MeV/c^2)=(368.2±2.5_(stat)±3.3_(sys))×10^(-10).The cross section is measured of e^+e^-→π^+π^- in the energy range between 600 and 900MeV/c^2 with a 2.93fb^(-1) data set taken at the center-of-mass energy 3.773 GeV at BESIII.The initial state radiation technique is used,and the total systematic uncertainty is estimated to be 0.9%.The squared form factor|F_π|~2 is extracted,and comparisons are made with results from both KLOE and BaBar. The two-pion contribution to the hadronic vacuum polarization contribution to(g-2)_μ is calculated to be a_μ^(ππ,LO)(600~900 MeV/c^2)=(368.2±2.5_(stat)±3.3_(sys))×10^(-10).

关 键 词：缪子反常磁矩 真空极化 初态辐射 

分 类 号：O572.33[理学—粒子物理与原子核物理]