Meson form factors and P→γγ physics at BESIII

FAIRNESS 2016

Pettersson, J.^1

Department of Physics and Astronomy, Uppsala University, Box 516, Sweden^1

关键词: Centre-of-mass energies;    Energy ranges;    Form factors;    Gammagamma;    Integrated luminosity;    Leading orders;    Radiative return;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/742/1/012012/pdf
DOI  :  10.1088/1742-6596/742/1/012012

来源: IOP

【 摘 要 】

Using data consisting of 2.93 fb-1integrated luminosity at the centre of mass energy √s = 3773 MeV, recorded with the BESIII detector at BEPCII, the cross section and form factor |Fπ|2was extracted in the energy range 600-900 MeV, using the method of radiative return. The cross section is used as input to calculate the leading-order vacuum polarisation contribution of the e+e-→π+π-channel to (g - 2)μ as aμππ,LO(600 - 900 MeV) = (368.2±2.5stat±3.3sys) • 10-10. This result is compatible with corresponding values using KLOE data, but disagrees whit BaBar. The ongoing search for e+e-→ηcat BESIII is also discussed.