Figure 5:  2-D Time-of-Flight (TOF) Distributions.  The horizontal axis shows the TOF between the production target and the counter S1 relative to the 50 MHz accelerator time structure.  The vertical axis shows the TOF between the counters S1 and S3.
(a) Pion Run:  All magnets are set for 150 MeV/c particles. The timing window defines the pion events (2·10^-6 events/sec).
(b) Decay Muon Run:  The pion transport section is set for 150 MeV/c and the spectrometer is set for 113 MeV/c.  The timing window defines the X-candidate muon events (0.05 events/sec).