Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Inexpensive neutron source
Date: Oct 25, 4:49 pm
Poster: Richard Hull

On Oct 25, 4:49 pm, Richard Hull wrote:


>These are intended to be used at several amps of current and modest voltage (~150 watts total power), but will tolerate high voltage and low current (at least it has remained intact so far). Since neutron output is largely a function of current, once the voltage threshold has been reached, you will not get a super high flux - but I am getting an impressive several hundred times background levels (measured with a BF detector).
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>More fun than a Sharper Image plasma globe!
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>Jones

This is rather hard to believe, but I haven't done the experiment yet. I have several of these lamps. The UV output is very high and they are used to supply UV or spectrally pure, narrow band light in special spectrographic situations.

They normally have a fillament and have about 36 volts impressed across the cathode and anode run at a few amps, but require a strike voltage of between 500 and 1000 volts. They are small arc lamps with very small apertures and quartz windows.

Deuterium requires a fixed and well known threshold to fuse based on cross section or temperature. None of these are even remotely reached in the deuterium lamp. The current has no meaning in this as the voltages involved with the arc anode to cathode are tens of thousands of volts to low. The gas temperature in the hot arc is on the order of several thousands of degrees at most. Again, way outside of the thermal criteria as well.

I will endeavor to check this out as well.

Be wary of RF noise in the arcing lamp driving the nearby BF3 counter. These counters would rather count anything other than neutrons!!! I am serious as a heart attack about this statement. Never blindly trust a neutron counter to count actual neutrons.

Richard Hull
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