Time of flight detector

Patent Granted A time of flight (TOF) detector is a particle detector which can discriminate between a lighter and a heavier elementary particle of same momentum using their time of flight between two scintillators. The first of the scintillators activates a clock upon being hit while the other stops the clock upon being hit. If the two masses are denoted by m_1and m_2 and have velocities v_1 and v_2 then the time of flight difference is given by \delta t = L\left(\frac{1}{v_1}-\frac{1}{v_2}\right)\approx \frac{Lc}{2p^2}(m_1^2-m_2^2) where L is the distance between the scintillators. The approximation is in the relativistic limit at momentum p and c denotes the speed of light in vacuum. Usually, \delta t is the apparatus' time resolution (~200 ps).