05/11/2011

Go Back

Because is something wrong I decided to measure the counts rate as function of threshold energy. Maybe my threshold was incorrect.

Below are my results for n's detector with HAMAMATSU PMT (-1500 V):

So it looks like my previous threshold value (-500 V) was not good. Let's set it up the -200 V. And see what happens.

The same set up as before, the distances are the same:

First he CF-243 source is far far away (sealed in the safe):

	counts/min (1 min test)	counts/min (1 min test)	counts/min (1 min test)	counts/min (1 min test)	avg counts/min
PS1
PS2
n's

Now the CF-243 source is on the top of PS1:

	counts/min (1 min test)	counts/min (1 min test)	counts/min (1 min test)	counts/min (1 min test)	avg counts/min
PS1	378,893	378,612	377,909	378,665	378,519.7
PS2	22,729	22,819	22,572	22,530	22,662.5
PS1+PS2	1044	1021	1023	975	1015.7
n's	200	210	228	219	214.2