User name X. Zheng
Log entry time 02:53:32 on July21,2001
Entry number 66955
keyword=False asymmetry check from cosmic and unpolarized target dataHere is a summary of false asymmetry study:
(1) using early production runs (pseudo-random mode),
no deadtime correction has been applied;
use cut in second timing peak to select cosmic events;
use cut in track number to select one track events;
use T1+T2 or T3+T4
left arm: 1618 +/- 482 ppm; right arm: -2320 +/- 458ppm
use only T1 or T3
left arm: 1503 +/- 482 ppm; right arm: -2385 +/- 458ppm
(2) same as (1), but use scalers to correct deadtime:
use T1+T2 or T3+T4
left arm 1539 +/- 482 ppm; right arm: -2212 +/- 467 ppm
use only T1 or T3
left arm: 1442 +/- 482 ppm; right arm: -2265 +/- 467 ppm
(3) using unpolarized target runs on july 17, (toggle mode),
no deadtime correction has been applied;
use cut in abs(react_z) < 0.15cm to reject cosmics;
use cut in track number to select one track events;
use T1+T2 or T3+T4
left arm: 2240 +/- 1016 ppm; right arm: 156 +/- 1037 ppm
use only T1 or T3
left arm: 2236 +/- 1016 ppm; right arm: 165 +/- 1037 ppm
Note: I found a mistake in my code about reading scalers from
right arm, so the asymmetry for right arm is different from
what I put in entry #65750.
Attached is a plot for unpolarized target runs, only four runs
(reference N2 and reference He3) have been analyzed for each
arm.
FIGURE 1
