Study of the process $e^+ e^- \to p \bar p$ via initial state radiation at BESIII

The Born cross section for the process e+e-→pp¯ is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an integrated luminosity of 7.5 fb-1, collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process e+e-→pp¯ and the proton effective form factor are determined in the pp¯ invariant mass range between 2.0 and 3.8 GeV/c2 divided into 30 intervals. The proton form factor ratio (|GE|/|GM|) is measured in 3 intervals of the pp¯ invariant mass between 2.0 and 3.0 GeV/c2.

Particle Physics Experiments
electron positron: annihilation
electron positron: colliding beams
radiation: initial-state interaction
p: form factor: ratio
initial state
Born approximation
tree approximation
mass spectrum: (p anti-p)
BES

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