Photon flux proportionality: Difference between revisions
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If we compare the photon flux from the two runs with DU target | If we compare the photon flux from the two runs with DU target | ||
run 2467 | run 2467 (7770 positrons total) | ||
[[File:flux_DU_r2467.png | 400 px]] | [[File:flux_DU_r2467.png | 400 px]] | ||
| Line 7: | Line 7: | ||
and | and | ||
run 2506 | run 2506 (30312 positrons total) | ||
[[File:flux_DU_r2506.png | 400 px]] | [[File:flux_DU_r2506.png | 400 px]] | ||
The average photon flux increased from 90 <math>e^+/min</math> to 350 <math>e^+/min</math> and the ratio is 350/90 = 3.9 . | The average photon flux increased from 90 <math>e^+/min</math> to 350 <math>e^+/min</math> and the ratio is 350/90 = 3.9 . | ||
In other way if we look at the integral number of positrons produced during the runs 30312/7770 = 3.9 | |||
The number of neutrons used to do narmalization, i.e. the sum of the number of neutrons in three detectors placed at 0 deg left, 90 deg bottom and 0 deg right changed as follows: | The number of neutrons used to do narmalization, i.e. the sum of the number of neutrons in three detectors placed at 0 deg left, 90 deg bottom and 0 deg right changed as follows: | ||
Revision as of 17:25, 10 June 2013
If we compare the photon flux from the two runs with DU target
run 2467 (7770 positrons total)
and
run 2506 (30312 positrons total)
The average photon flux increased from 90 [math]\displaystyle{ e^+/min }[/math] to 350 [math]\displaystyle{ e^+/min }[/math] and the ratio is 350/90 = 3.9 .
In other way if we look at the integral number of positrons produced during the runs 30312/7770 = 3.9
The number of neutrons used to do narmalization, i.e. the sum of the number of neutrons in three detectors placed at 0 deg left, 90 deg bottom and 0 deg right changed as follows:
run 2467: SUM(0-90-0) = 518 neutrons
run 2506: SUM(0-90-0) = 2195 neutrons
The neutron number ratio is 2195/518 = 4.2 .
That means that photon flux monitor can be used for the purpose of relative normalization.