Timing properties of long scintillation counters based on scintillating fibers

The light output and timing characteristics of a scintillation counter constructed of plastic scintillating fibers are compared to those of a counter with identical transverse cross section of 2 cm × 3 cm made of bulk scintillator. It is shown that the timing resolution at long distances is better for the fiber than for the bulk scintillator. The improvement is a factor of 1.8 at a distance of 2 m from the phototube.