Difference between revisions of "Conversion TDC to Energy"
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Revision as of 06:59, 18 November 2008
When electron beam hit the radiator, TDC start to count. It will take gamma 14 ns to reach the target. Then after some time, neutron arrive to the detectors.
Let's call the the total time from electron beam hit the radiator to neutron to be detected is. So,
where d is the distance between detector and target, v is speed of neutron. So,
where should be in the unit of nano second.
For data go to link:
or click on:
Method 2: Using time difference in two peaks
If we assume gamma flash is coming from target, then by time difference in gamma peak and neutron peak, we can tell the energies in neutrons.
: Neutron time of flight
: Gamma time of flight
d: Distance between detector and target.
d for polarized case:= 91.25 inches = 231.775 cm.
d for unpolarized top detector:=96.25 inches = 244.745 cm.
d for unpolarized side detector:=91.39 inches = 232.131 cm.
For data go to Link below:
or click on:
Energy vs Channel
We calibrated ADC [] and using those data we can tell energy of neutron by its relative channel number difference from gamma peak.
There a two scale for ADC. One is 2000 ns, the other one is 4000ns.
For 2000 ns scale:
For 4000 ns scale: