A FIBER OPTIC ARRAY DETECTOR

WIRE CHAMBERS ARE A CLASS OF PARTICLE TRACK DETECTORS THAT HAVE FOUND WIDE APPLICATIONS IN HIGH ENERGY PARTICLE PHYSICS EXPERIMENTS. LARGE WIRE CHAMBER DETECTORS HAVE BECOME RATHER COMPLEX, REQUIRING MANY FAST ELECTRONIC CIRCUITS. THIS INVESTIGATION OFFERS THE POTENTIAL OF SIMPLIFICATION AND COST REDUCTION FOR LARGE WIRE CHAMBER DETECTORS. THE PHASE I EFFORT IS INVESTIGATING THE FEASIBILITY OF USING THE KERR EFFECT TO PROVIDE POSITIONAL INFORMATION BY USING AN ARRAY OF OPTICAL FIBERS IMMERSED IN A KERR MEDIUM. THE TECHNIQUE BEING INVESTIGATED DEPENDS ON A CHANGE IN THE REFRACTIVE INDEX INDUCED BY PASSAGE OF AN IONIZING PARTICLE IN A KERR MEDIUM NEXT TO AN OPTICAL FIBER. IF THE RESULTING REFRACTIVE INDEX IS CLOSE TO THAT OF THE FIBER, ANY LIGHT SIGNAL PASSING THROUGH THE FIBER WILL BE INTERRUPTED. A STROBE LIGHT PULSE AT THE TIME OF AN EXPECTED EVENT WILL THUS BE REDUCED OR CUT OFF. A METHOD OF REDUCING THE COST AND COMPLEXITY OF PROCESSING THE SIGNALS OF A LARGE OPTICAL FIBER ARRAY IS ALSO BEING STUDIED. THE STROBE LIGHT SIGNALS FROM A NUMBER OF FIBERS ARE FED INTO A SINGLE FIBER WITH INDIVIDUALLY DIFFERENT DELAYS PROVIDED BY FIBER COILS OF DIFFERENT LENGTHS. THE OUTPUT IS THUS A STRING OF PULSES ARRIVING AT DIFFERENT TIMES. THE PASSAGE OF A CHARGED PARTICLE NEXT TO ANY FIBER RESULTS IN THE SUPPRESSION OF THE CORRESPONDING STROBE PULSE.