First phase of BEPCII complete

摘要

The first phase of commissioning BEPCII, the major upgrade of the Beijing Electron-Positron Collider (BEPC) came to a successful conclusion on 3 August, when the beam current reached 500 mA at 1.89 GeV. On the same day the researchers also completed mapping the combined magnetic field of the superconducting insertion magnets (SCQs) and the superconducting solenoid of the detector BESIII. This followed a series of studies that included the first collisions between beams in the electron and positron rings. The successful commissioning of the superconducting magnets and the cryogenics demonstrated that both systems were stable and up to design performance.