A SIMPLE SUPERCONDUCTING ELEMENTARY-CHARGE POLARITY DETECTOR

A NOVEL DETECTOR CAPABLE OF IDENTIFYING THE ELECTRIC CHARGE OF A SINGLE RELATIVISTIC ELEMENTARY PARTICLE IS PLANNED. THE DETECTOR MEASURES THE MAGNETIC FIELD GENERATED BY THE PARTICLE BY ALLOWING THIS MAGNETIC FIELD TO INDUCE A CURRENT IN A SUPERCONDUCTING LOOP. THE EXISTENCE AND SIGN OF THE LOOP CURRENT, AND HENCE THE POLARITY OF THE ELECTRIC CHARGE, ARE THEN IDENTIFIED USING A SUPERCONDUCTING COMPARATOR. THE HIGH SENSITIVITY REQUIRED TO ENABLE SUCH A MEASUREMENT IS ACHIEVED BY THE USE OF AN ARRAY OF LOOPS CONFIGURED AS A DETECTING ANTENNA, AND RESULTING IN A CURRENT PULSE WHICH CAN BE DETECTED WITH THE DEMONSTRATED ULTRAHIGH SENSITIVITY OF SUPERCONDUCTING CIRCUITS. THE COMPLETE DETECTOR CAN BE FABICATED MONOLITHICALLY ON A SINGLE SUBSTRATE, AND ALLOWS DENSE PACKING OF A LARGE ARRAY. THIS DETECTOR, WHEN USED IN COMBINATION WITH ENERGY MEASURING CALORIMETERS, CAN REPLACE THE SPATIAL TRACKING DETECTORS CURRENTLY USED IN HIGH ENERGY ACCELERATORS TO DETERMINE THE MOMENTUM OF PARTICLES (AND HENCE THEIR CHARGE POLARITY). THESE TRACKING DETECTORS INCREASE SIGNIFICANTLY IN SIZE, WEIGHT, AND COST, AS THE ENERGY OF THE EXPERIMENTS INCREASES, AND EVENTUALLY BECOME UNABLE TO RESOLVE THE CHARGE OF THE PARTICLES. THE PLANNED DETECTOR WILL RESULT IN SIGNIFICANT SAVINGS IN SIZE, COST, AND WEIGHT. PHASE I WILL DEMONSTRATE THE FEASIBILITY OF THE PRINCIPLE BY SHOWING THE SUPERCONDUCTING CIRCUIT CAPABLE OF RESOLVING THE CURRENT PULSE RESULTING FROM THE MAGNETIC DETECTION OF A SINGLE PARTICLE. IN PHASE II, THE CIRCUIT WILL BE COMBINED WITH THE DETECTING ANTENNA AND DEMONSTRATED IN AN ACTURAL ACCELERATOR.