05/12/2011 2n correlation test
The voltages and thresholds are:
| PMT voltage, V | threshold, mV | discr. width, ns | |
|---|---|---|---|
| PS1 | -1000 | -80 | 20 |
| PS1 | -1000 | -80 | 10 |
| n's | -1100 | -200 | 20 |
The powers are:
PS1 and PS2: -1000 V (the old 2-channel TENNELEC TC952) n's: -1100 V (the new 2-channel C.A.E.N N471)
The thresholds are:
PS1 and PS2: -80 mV n's: -200 mV
The discriminator widths are:
PS1: -20 ns PS2: -10 ns n's: -20 ns
Let's do the 2n correlation test with CF252 source. The voltages and thresholds are the same.
First the set up is like:
- ○ PS1 and PS2 are parallel to each other and are faced to the source.
- ○ the CF252 source in the middle
- ○ the distance between PS1(PS2) and source is 6 cm
The total number of events (2n fission events + random coincident) are:
| total counts | time | counts/min | counts/sec | |
|---|---|---|---|---|
| PS1 | [math]\displaystyle{ 255977\pm505.9 }[/math] | 10 min | [math]\displaystyle{ 25597.7\pm50.6 }[/math] | [math]\displaystyle{ 426.63\pm0.84 }[/math] |
| PS1 | [math]\displaystyle{ 421917\pm649.5 }[/math] | 10 min | [math]\displaystyle{ 42191.7\pm64.9 }[/math] | [math]\displaystyle{ 703.19\pm1.08 }[/math] |
| PS1+PS2 | [math]\displaystyle{ 1224\pm34.9 }[/math] | 10 min | [math]\displaystyle{ 122.4\pm3.5 }[/math] | [math]\displaystyle{ 2.04\pm0.06 }[/math] |
Second the set up is like:
- ○ PS1 and PS2 are perpendicular to each other and are faced to the source.
- ○ the CF252 source in the middle
- ○ the distance between PS1(PS2) and source is 6 cm
The total number of events (2n fission events + random coincident) are:
| total counts | time | counts/min | counts/sec | |
|---|---|---|---|---|
| PS1 | [math]\displaystyle{ 250116\pm500.1 }[/math] | 10 min | [math]\displaystyle{ 25011.6\pm50.0 }[/math] | [math]\displaystyle{ 416.86\pm0.83 }[/math] |
| PS1 | [math]\displaystyle{ 414774\pm644.0 }[/math] | 10 min | [math]\displaystyle{ 64.4\pm64.9 }[/math] | [math]\displaystyle{ 691.29\pm1.07 }[/math] |
| PS1+PS2 | [math]\displaystyle{ 1359\pm36.9 }[/math] | 10 min | [math]\displaystyle{ 135.9\pm3.7 }[/math] | [math]\displaystyle{ 2.26\pm0.06 }[/math] |