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: comparative neutron production rates
Date: Jun 26, 2:35 pm
Poster: Larry Cress

On Jun 26, 2:35 pm, Larry Cress wrote:

>For comparison purposes, a thick heavy water ice target bombarded by accelerated deuterons yields 3E7 n/sec/uA beam current at 200 kev. They mention that yield goes as square of accelerating potential up to 1 Mev. I guess this means that the potential drop accelerator in "the Amateur Scientist" running D into a D20 target would be making bunches o' neuts because it is in this range (at least voltage wise, I don't know how much beam current you could get.. I get 25 uA from the VanDeGraaf at that voltage)

I constructed the Van de Graaff accelerator described in the August 1971 Scientific American, which is apparently being referred to here. I measured about 50 million neutrons per second with a 10 microamp deuteron beam, but the beam was not pure monoatomic deuterons. If anyone has questions about producing neutrons via this more conventional technique, I would try to answer them.

Although it has been correctly stated that deuterium is an uncontrolled material, it should be noted that production of neutrons using accelerated deuterons is a regulated activity in most states. Most, if not all, states have a Radiation Control Act which regulates accelerators. They would likely consider IEC fusor type devices acclerators since a high potential drop is used to acclerate ions in a vacuum.

I continue to be amazed by the resurgence of interest in hobbyist accelerators, as evidenced by these postings. Keep on fusin', but be wary of those x-rays and neutrons.