BES III
The Beijing Spectrometer III (BESIII) is the central multi-purpose detector at the Beijing Electron-Positron Collider (BEPC-II), which is operating in the range of center-of-mass energies between 2.0 and 5.0 GeV (so-called tau-charm-factory). The accelerator BEPC-II is located on the campus of the Institute of High-Energy Physics (IHEP).
Since 2016 it has achieved (and recently even exceeded by 10%) the design luminosity of $\rm 10^{33} cm^{−2}s^{−1}$. BESIII has collected the world’s by far largest data sample in this energy region and is currently in the process of increasing the data sample at a center-of-mass energy of 3.77 GeV to 20 $\rm fb^{-1}$. In 2024, the accelerator will carry out an upgrade with the goal to increase the luminosity at high energies and, furthermore, the maximum center-of-mass energy will be increased to 5.6 GeV. After the machine upgrade, BESIII is expected to run for at least another 10 years.