Project C: Hidden charm exotics at BESIII

Project leader: Prof. Dr. Klaus Peters

Search for additional hidden charmonium states and study the Y (42604360) line shape. This shall be performed by the investigation of semi inclusive production cross-sections in e+e annihilations in the centre-of-mass energy range between 4.1 and 4.6 GeV. The energy dependent semi inclusive measurements are performed using recoil techniques as mentioned in the introduction.

To be as complete as possible, we propose in particular the following recoil channels for √s = 4.18, 4.23, 4.26, 4.36, 4.42, 4.60 GeV each.

  1. Investigation of light quark recoil spectra
  2. Investigation of J∕ψ recoil spectra
  3. Investigation of baryon recoil spectra
  4. Investigation of open charm recoil spectra
  5. Further development of the physics program of BESIII as well as participation in data
    taking and quality assurance

Although the cross-section themselves are already important for a understanding of the Y (42604360) decomposition and the nature of the contained state, any formerly unknown structure would be an incommensurable source of new information. In total 11.2 fb1 of data is already available and more may come in upcoming data taking periods.