5.4 Extraction of the branching ratio R

Figure 5.6: Timing spectrum using the prompt trigger. Time increases to the left with the TDC start occurring at approximately channel 100. The 20 ns beam structure is clearly seen caused by particles in beam buckets subsequent to the one which created the trigger.

which account for the specifics of the experimental method. Most of these corrections are needed to account for the µ⁺ -> e⁺ n n (hereafter referred to as Michel) events not recorded by our detector. These include a factor R_ts to match the amplitude of background and signal spectra, a factor R_lh to account for all the low energy Michel events not recorded by the high-threshold trigger, a correction f^-1 for the experimental gate timing,

Figure 5.7: Timing spectrum for prompt events in the DPG. Time increases to the left with the TDC start occurring at approximately channel 100. The 20 ns beam structure is present similar to figure 5.6.

and a factor R_lo low energy tail correction. A description for each term and how it was obtained is presented below.

• 5.4.1 Determination of the "raw" ratio Rraw
• 5.4.2 Determination of the correction Rts
• 5.4.3 Determination of the correction factor Rlh
• 5.4.4 Determination of the gate timing correction f-1
• 5.4.5 Determination of the low energy tail correction
• 5.4.6 Evaluation of the branching ratio