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 for 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 indicate a mean detected yield of about 10 photoelectrons per fiber, position resolution of 140 /spl mu/m for a fiber doublet, and a doublet efficiency greater than 99%.<
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