Photon flux proportionality

If we compare the photon flux from the two runs with DU target

run 2467

and

run 2506

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 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.