Performance of a large scale scintillating fiber tracker using VLPC readout

A large scale scintillating fiber tracker using visible light photon counter (VLPC) readout was built as a prototype far the upgraded DO central tracker. This prototype has been under test at Fermilab for six months using cosmic rays. A description of the components of the tracker including the photodetector, fibers, lightguides, ribbons, and DAQ is given. Preliminary results on detected photon yield, position resolution, efficiency and VLPC performance are presented.<
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