Discriminating neutron peaks from electrical noise peaks
Posted: Mon Jan 13, 2020 6:51 pm
As discussed here previously, and in my own experience as well, counting neutrons using a Helium-3 detector is fraught with difficulty due to electrical pulses from arcing in a fusor. There are sophisticated methods to do peak discrimination, but I just came across a clever solution that makes use of the pulse width triggering capability of a digital oscilloscope. I was reading a recent thesis from Khachan’s group in Sydney by Richard Bowden-Reid (https://ses.library.usyd.edu.au/handle/2123/21070) and noted that he connected his preamp output to a Rigol 1074Z oscilloscope set to trigger on pulses 2-5 microseconds in duration. He then simply connected a digital counter to the oscilloscope’s TTL trigger output to count neutrons. I was excited to try this until I discovered my Tektronix scope does not have a TTL trigger output. Given that Chinese digital scopes are available at very good prices, it could be worth buying one solely for this function.