PA-PRO-2017-016

The PANDA experiment is a fixed target experiment where antiprotons collide with stationary hydrogen atoms. The main physics program of the experiment is to study open questions in hadron physics by performing charmonium spectroscopy by precise measurements of width, mass and decay branches and investigating possible exotic states like glueballs and hybrids. The Barrel Time-of-Flight detector (Barrel TOF), which is built in the PANDA target spectrometer, located between the DIRC detector and the EMC, has been designed to precisely measure the time at which a charged particle transits the detector with a resolution superior to the other sub-detectors of PANDA. A time resolution below 100 ps (sigma) is mandatory for this sub-detector to fulfill the requirements of good event separation and particle identification below the Cherenkov threshold. The implementation of the Barrel TOF is based on very fast organic scintillator tiles with a size of 87x29.5x5 mm3 coupled to Silicon Photomultipliers. The total of 1920 tiles are read out each by 8 SiPMs and cover almost the full azimuthal angular range and polar angles from 22.5 deg to 140 deg and an area of about 5 m2. The current prototypes achieve ~60 ps, well below the design goal. The detector R&D is now in a matured stage.