Scintillating Optical Fibers for Fine Grained Hodoscopes

Fast detectors with fine spatial resolution will be needed to exploit high event rates at ISABELLE. Scintillating optical fibers for fine grained hodoscopes have been developed by the authors. A commercial manufacturer of optical fibers has drawn and clad PVT scintillator. Detection efficiencies greater than 99% have been achieved for a 1 mm fiber with a PMT over lengths up to 60 cm. Small diameter PMT´s and avalanche photodiodes have been tested with the fibers. Further improvements are sought for the fiber and for the APD´s sensitivity and coupling efficiency with the fiber.