Belle is an experiment at the KEK B-factory.
The Belle experiment was built at KEKB accelerator, which is located at the High Energy Accelerator Research Organisation (KEK) in Tsukuba, Ibaraki Prefecture, Japan. The experiment ran from 1999 until 2010. KEKB is electron-positron asymmetric energy collider. The original objective of Belle experiment was to measure precisely differences between particles and anti-particles in the B system. Most of the Belle luminosity was recorded on or near ϒ(4S) resonance, which is optimal centre of mass (CM) energy for production of BB pairs. The main objective was achieved and after collecting 1000fb-1 of data at various ϒ resonances Belle obtained many others physics results.
Experiment Belle was designed and optimized for observation of CP violation(CP standing for Charge Parity) in B meson system. The results of Belle measurements were consistent with the theoretical proposal of Kobayashi and Maskawa and this results led to Physics Nobel Prize in 2008. Besides the topics of B physics, Belle experiment also contributed to area of charm physics, tau lepton physics, hadron spectroscopy and others. Our group studies indirect CP violation and also unitary triangle phi3=gamma angle (more info in the works of Z. Drasal and D. Cervenkov).
The Belle II experiment represents the comprehensive update of the experiment and will run on SuperKEKB accelerator, the new version of KEKB. The main contribution of our group at Institute of Particle and Nuclear Physics is participation on preparation of the pixel detector DEPFET (more info), development of the software description of the pixel (PXD) passive material, description of the strip (SVD) passive material for Belle II and GRID computing of Monte Carlo Simulations on the computing centres in Prague.
There are many opportunities for a student engagement and various thesis. These are described at the Czech version of this page.
J. Brozicka et. al.: Physics Achievements from the Belle Experiment(arXiv:1212.5342)