The studied problem and the main goal of research:
The main task of the BES-III experiment is to study the properties of charmonium and charmed mesons-particles, which include the charmed quark.
The main purpose of the BES-III experiment at the electron-positron collider BEPC-II (IHEP, China Academy of Sciences, Beijing) is the precision measurement of the production of tau-lepton pairs and charmonium resonances. The experimental problems include the spectroscopy of light hadrons, the study of the spectrum and transitions in the charmonium system, the measurement of the properties of D and Ds mesons and tau-leptons, and the search for new states above the production threshold of particles with an open charm. The data set has been conducted since 2009. The world’s largest event statistic was obtained with the formation of J / psi, psi (3686), psi (3770), psi (4040) resonances, scanning in the energy range 2.0-4.6 GeV, a set of unique data in the region 4, 2-4.6 GeV for the study of XYZ states.
Expected results after the completion of the stages of a theme or projects:
- Precise verification of the predictions of Quantum chromodynamics ( QCD )and the Standard Model in the leptonic decays of charmed mesons.
- Refinement of the properties of poorly studied charmonium states and the search for new transitions between them.
- Search for exotic (XYZ) states, the study of their properties and the establishment of their nature.
- Study of the spectrum of light hadrons. Search for exotic conditions (glueballs, hybrids, multiquarks). Solution of the problem of “extra” meson and “missing” baryon states.
- Measurement of the R ratio in the range 2.0-4.6 GeV
- Measurement of the mass of the tau lepton with high accuracy.
Expected current results by stages of a theme or projects:
- Analysis of data from the BES-III experiment.
- Development of the software for the experiment.
- Integration of cloud resources into the distributed computing system of the BES-III experiment.
- Creation of software for partial-wave analysis using the HybriLIT cluster.
Measurement of the mass of the tau lepton with high-precision .