Aug 22, 2003, by Seonguk Jin and Dave Mack
Preliminary timing windows have been obtained using run 47011, a high rate run from the first luminosity scan early in the FpiII experiment. Most of the SOS tracks are pions. Outstanding issues are whether these windows will work for the whole FpiII experiment (that still needs to be checked), and why the efficiency at zero rate isn't a bit higher (do we have a parameter screwed up somewhere?).
1. sdc.param File containing the time windows. We have chosen a 500 unit (= 250 nsec) wide window.
2. Overlay of raw and cut times
Shows that
we're not cutting anything out, and we have left about 50 units (= 25 nsec) of slop on each side to allow for extreme
variations in drift velocity.
3. Efficiency vs window width and offset
Shows that our conservative window (light blue, 500) is reasonable. The sensitivity to noise hits doesn't seem to be as
great as in the HMS.
4. Efficiency versus rate Shows the rate dependence of the tracking efficiency. While the efficiency at high S1 rates is excellent, the efficiency extrapolated to zero rate is only about 98% which is .5% lower than we saw in FpiI in 1997.