Measurements of the center-of-mass energies at BESIII via the di-muon process

Abstract

From 2011 to 2014, the BESIII experiment collected about 5 fb(-1) data at center-of-mass energies around 4 GeV for the studies of the charmonium-like and higher excited charmonium states. By analyzing the di-muon process e(+)e(-)->gamma ISR/FSR mu(+)mu(-), the center-of-mass energies of the data samples are measured with a precision of 0.8 MeV. The center-of-mass energy is found to be stable for most of the time during data taking.