Beijing Electron–Positron Collider II


The Beijing Electron–Positron Collider II is a Chinese electron–positron collider, a type of particle accelerator, located in Beijing, People's Republic of China. It has been in operation since 2008 and has a circumference of 240.4 m.
It was intended as a charm factory and continues the role CLEO-c detector. The center of mass energy can go up to 4.6 GeV with a design luminosity of 1033 cm−2·s−1. Operations began in summer 2008 and the machine has run at multiple energies.

BES III

The BES III is the main detector for the upgraded BEPC II.
BES III uses a large superconducting solenoid to provide a 1-tesla magnetic field, and also features a helium gas-based tracking chamber and an electromagnetic calorimeter using 6240 caesium iodide crystals.