Time and Energy Resolution of LYSO and SiPM Detectors for Testing CP Conservation

We will be testing charge conjugation parity (CP) conservation in positronium (Ps) decay. To do this we will use silicon photomultipliers (SiPM) and Lu_1.9Y_0.1SiO₅ (LYSO) scintillation crystals to detect Ps annihilation radiation. I developed a procedure to test the timing and energy resolutions of our detectors. I created a testing setup that holds our detectors and a source of radiation. I developed a method for offline constant fraction discrimination (CFD) from a digitized SiPM signal. From this we obtain a coincidence pulse time difference histogram. We determine time and energy resolution by fitting gaussians to peaks in the time and energy histograms. Details of the CFD method and results will be presented.