Hi Guys,
I learnt something new today..., one can measure ion temperature in pulsed D+D fusion by measuring the neutrons.
Apparently that is what they do at Lawrensville (LPPX), by measuring the arrival time of the neutrons from each pulse, they can determine the ion temperature inside the plasma.
Neutrons from the D+D reaction are monoenergetic, which means that they are always produced with the same energy 2.45 mev. however within the plasma ions are moving in all directions, so some are moving towards the detector and others are moving away from the detector, therefore when they fire a shot, some neutrons arrive early and some arrive late, and by looking at the width of the bell curve, it is possible to deduce the plasma temperature.
The neutron velocity varies with the square root of the energy...
E = mv^2
v = sqrt(e/m)
...assume M = 1
sqrt(2,400,000 ev)
------------------------ = + or - % of Neutron velocity.
sqrt(ion energy)
The neutron velocity can be measured by knowing the time of the shot and the distance from the experiment to the detector.
Steven
Measuring Ion Energies with Neutrons
- Steven Sesselmann
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Measuring Ion Energies with Neutrons
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
Re: Measuring Ion Energies with Neutrons
Interesting Steven - thanks
- Steven Sesselmann
- Posts: 2128
- Joined: Wed Aug 10, 2005 9:50 pm
- Real name: Steven Sesselmann
- Location: Sydney - Australia
- Contact:
Re: Measuring Ion Energies with Neutrons
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG