Physics of Charm Project of the SFB/TRR55


Theoretical studies of the properties of hadrons containing charm quarks have a number of motivations. For example, the semi-leptonic decays of D mesons can be used to constrain elements of the CKM matrix, contributing to the search for inconsistencies in the Standard Model of particle physics, while calculations of the decay constant of the Ds meson can be used to constrain the size of Beyond the Standard Model contributions. Furthermore, there has been a lot of interest in the spectroscopy of charmonium, D and Ds systems due to the discovery of many new experimental states, such as the X(3872), Y(4260) and Z(4430) charmonium states and the Ds0(2317) and Ds1(2460) mesons. Not all states can be fitted into a quark model meson picture. Several states are close to decay thresholds and are likely to have significant non-quark model components. The Z(4430) certainly must contain at least four quarks, as it is charged.

Many experiments are dedicated to studying charm physics, with data analysis of completed experiments, Babar, Belle, CLEO-c and the Tevatron, still continuing. Existing experiments, BES III and the LHC, will generate data for many years to come and further experiments are planned, PANDA at FAIR, SuperKEKB and SuperB. To fully exploit the experimental results, non-perturbative (lattice) QCD calculations are needed. See Links for reviews, experiments and other relevant sites.

The Physics of Charm project is a collaboration between lattice QCD researchers at the University of Regensburg and the University of Wuppertal. The project is supported by SFB/TR55 Hadron Physics from Lattice QCD.

Project Areas

  • Decay constants and form factors for heavy-light and flavour changing currents.
  • Spectroscopy of mesons and baryons containing charm quarks.
  • Near threshold states and mixing with flavour singlets.
  • Electromagnetic transition rates of charmonia.

Selection of results

Preliminary mass spectrum of the Ds system on nf=2+1 configurations (arXiv:1108.6147).

Charmonium and D-anti-D molecular spectra on nf=2 configurations (arXiv:1110.2381)

Preliminary results for the form factors for the decay of the D meson to flavour singlets on nf=2+1 configurations (arXiv:1111.4053)