We define the muon spin polarization along the counter axis as
, where is the time evolution of
the muon spin angle relative to the counter axis (see Fig.8).
The positron count rate of each counter
Ni(t) (i=1,2) is found by integrating the positron angular
distribution of this tilted muon spin over the counter solid angle
and positron energy. The answer becomes:
The muon spin polarization , which is the information one would like to obtain from the SR technique, is calculated by taking the corrected asymmetry (eq.12), which is essentially the count difference of the two counters normalized by the total count:
In Fig.9, an example of the positron counts [N1(t)] and the corrected asymmetry  is shown. A Larmor precession of the muon spin is seen, as an external magnetic field perpendicular to the initial muon spin direction was applied during this measurement.
The next section presents more details of the experimental setup which is required for the SR measurements.