EmiT Collaboration: testing time reversal symmetry in neutron decay

EmiT is testing the Standard Electro-Weak Model by looking at a time-reversal invariant triple correlation in polarized neutron decay. Basically, we will measure which way the decay particles go when polarized neutrons decay, and we will compare our measurement to a calculation to test the Standard Model. This experiment first ran for seven months in 1998 when I was completing my post-doc at NIST. Detector failures limited our initial results, but a second and final 18 month run in 2002-2003 was very successful. The data will be analyzed over the next year. I am responsible for the magnetic field alignment and on-line monitoring of 50 parameters associated with magnetic fields, data rates, etc. Magnetic field alignment is required at the miliradian level over a 50 cm long, 6 cm diameter volume to avoid a significant systematic error. M. Freddie Dias, ’06 has been a great help during both the summer and the school year in analyzing the monitor data.