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After collecting all relevant data, the ratios R1, R2, and R3 were
calculated for each run. The results are given in
Tables 1, 2, and 3 respectively.
Table 1:
Elastic monitor counts normalized to Faraday cup reading
Run |
E |
Pressure |
FC4 (epA) |
Livetime |
Time (s) |
Elastics |
R1 |
7191 |
582.7 |
4.57 |
480 |
0.96 |
326 |
1421 |
702.2 |
7192 |
582.7 |
8.12 |
425 |
0.96 |
518 |
3726 |
740.6 |
7193 |
582.7 |
6.22 |
450 |
0.94 |
1160 |
6285 |
697.7 |
7194 |
582.7 |
6.21 |
430 |
0.92 |
748 |
4085 |
753.7 |
7202 |
471.9 |
5.82 |
387 |
0.90 |
696 |
4511 |
713.3 |
7210 |
784.2 |
7.42 |
350 |
0.95 |
2266 |
6696 |
740.1 |
7212 |
784.2 |
7.35 |
305 |
0.95 |
692 |
1758 |
734.6 |
7238 |
774.7 |
7.96 |
25 |
0.99 |
1150 |
203 |
540.4 |
7239 |
774.7 |
7.80 |
16 |
0.99 |
744 |
91 |
593.1 |
7240 |
774.7 |
7.80 |
17 |
1.00 |
394 |
21 |
242.2 |
7241 |
774.7 |
7.80 |
14 |
0.99 |
876 |
76 |
481.8 |
7242 |
774.7 |
7.86 |
13 |
0.99 |
1240 |
117 |
559.9 |
7243 |
774.7 |
7.73 |
15 |
0.99 |
1766 |
195 |
576.9 |
7244 |
774.7 |
7.77 |
13 |
0.99 |
2902 |
193 |
400.8 |
|
Table 2:
Elastic monitor counts normalized to beta monitor
Run |
E |
Pressure |
Charge Fraction |
Livetime |
Elastics |
Scaler |
R2 |
7191 |
582.7 |
4.57 |
0.34 |
0.96 |
61904 |
89.6M |
18.3 |
7192 |
582.7 |
8.12 |
0.46 |
0.96 |
103794 |
91.8M |
22.6 |
7193 |
582.7 |
6.22 |
0.40 |
0.94 |
39818 |
43.6M |
21.0 |
7194 |
582.7 |
6.21 |
0.45 |
0.92 |
58324 |
68.5M |
22.7 |
7202 |
471.9 |
5.82 |
0.41 |
0.90 |
71292 |
55.2M |
22.8 |
7210 |
784.2 |
7.42 |
0.50 |
0.95 |
37058 |
65.5M |
24.8 |
7212 |
784.2 |
7.35 |
0.47 |
0.95 |
16651 |
29.2M |
23.7 |
7238 |
774.7 |
7.96 |
0.50 |
0.99 |
3391 |
4.92M |
26.4 |
7239 |
774.7 |
7.80 |
0.51 |
0.99 |
981 |
1.42M |
27.3 |
7240 |
774.7 |
7.80 |
0.37 |
1.00 |
194 |
3.57M |
15.4 |
7241 |
774.7 |
7.80 |
0.45 |
0.99 |
3608 |
5.31M |
23.6 |
7242 |
774.7 |
7.86 |
0.53 |
0.99 |
2946 |
4.39M |
27.4 |
7243 |
774.7 |
7.73 |
0.42 |
0.99 |
1834 |
2.77M |
21.6 |
7244 |
774.7 |
7.77 |
0.46 |
0.99 |
1201 |
1.74M |
24.8 |
|
Table 3:
Beta monitor counts normalized to Faraday cup reading
Run |
E |
FC4 (epA) |
Charge Fraction |
Time (s) |
Scaler |
R3 |
7191* |
582.7 |
480 |
0.34 |
326 |
2.06M |
38.5 |
7192 |
582.7 |
425 |
0.46 |
518 |
3.09M |
30.7 |
7193 |
582.7 |
450 |
0.40 |
1160 |
7.07M |
34.1 |
7194 |
582.7 |
430 |
0.45 |
748 |
4.52M |
31.3 |
7202 |
471.9 |
387 |
0.41 |
696 |
3.43M |
30.8 |
7210 |
784.2 |
350 |
0.50 |
2266 |
12.0M |
30.2 |
7212* |
784.2 |
305 |
0.47 |
692 |
2.75M |
27.7 |
7238* |
774.7 |
25 |
0.50 |
1150 |
0.27M |
18.5 |
7239* |
774.7 |
16 |
0.51 |
744 |
0.12M |
19.4 |
7240 |
774.7 |
17 |
0.37 |
394 |
0.08M |
30.6 |
7241* |
774.7 |
14 |
0.45 |
876 |
0.14M |
25.3 |
7242* |
774.7 |
13 |
0.53 |
1240 |
0.17M |
19.8 |
7243* |
774.7 |
15 |
0.42 |
1766 |
0.32M |
29.1 |
7244* |
774.7 |
13 |
0.46 |
2902 |
0.39M |
22.7 |
* Data had unstable beta monitor readings.
|
|
One of the most striking results of this study is the drop in the value of R1
at 774.7 keV/u. Run 7240 has the most abnormally low value of R1,
possibly due to a statistical fluctuation in the elastic counts
(though this too is unclear). Even if we exclude this run, however,
all other runs at the energy show a significant decrease in R1
compared to those at 784.keV/u. There is no evidence of a strong
resonance at this energy, so it is unclear what could be causing this
anomaly. The beam intensity is fairly low at this energy, though, so
the FC4 readings may be approaching the level of noise, making the error
quite large.
R3 also had a large uncertainty associated with it. This may be
partially a result of unstable beta readings which occurred in eight out of the
fourteen runs (our time window was defined by the time in which the
elastic monitor counts, not the beta monitor counts, were constant).
Of the runs with stable beta readings, one included the anomalous run
7240. Left with only five reliable results, there does not seem to be
enough data to make any conclusions about the reliability of R3.
The most constant ratio proved to be R2. Its largest source of
deviation appeared to be caused by a scatter in the charge state
fraction F. If we assumed a constant F, however, the scatter
decreased, and if we omitted the outlier run 7240, R2 showed only a 3.7%
variation at 582.7 keV/u, and a 1.9% variation at 774.7 keV/u. A
constant value for R2 indicates that while the beam may fluctuate, the
counters are stable, and measure the same value to a few percent. As
energy increases, however, there appears to be a slight increase in
R2, making it uncertain whether this value will be useful
as a ``universal constant.''
Next: Recommendations
Up: BeamNormalization
Previous: Data Analysis
Catherine Neish
2003-03-12