Optical Simulation Studies of Particle Detector Design For Efficient Functioning

We have investigated and compared the effectiveness of two different particle detectors based on the light guide material and geometrical design to be utilized in MOLLER experiment at Jefferson Lab. This is done with a view of marking out the most efficient structure that can deliver optimum number of photoelectrons from the scattered electrons passing through the detector. Simulations are carried out with the plastic scintillator coupled to the photomultiplier tube (PMT) separately via polymethyl metacrylate (PMMA) based flat trapezoidal and optical fiber light guides. In the design of the former, PMT is mounted on the light-guide firmly attached to the polyvinyl-toluene based scintillator. For optical fiber coupled scintillator type, two strands of wavelength shifting fibers, terminated by pmt at both of their ends and with separation distance of 100mm between them, were thrusted into the grooves created across the back of the optical scintillator. From the preliminary results obtained, measurements conducted with plastic scintillator coupled through optical fiber to the PMT suggested the betterment of this technique in terms of photoelectron yield than measurement carried out when connected to PMT via flat trapezoidal light guide.