Understanding attenuation of potential ionising radiation in a Parkhomov style reactor

Understanding attenuation of potential ionising radiation in a Parkhomov style reactor.

[]=Project Dog Bone=[]

A concerned follower and very generous British donor called Stephen has made it possible for the project to acquire a full turn-key UCS30 spectrometer system which arrived yesterday at Alan's in California and was set up by him and MFMP volunteer Skip who has driven all the way down from Canada to help in a series of tests.

UCS30

The system comes complete with a set of check sources - detailed as

"A set of 8 sources including one each of Co-57, Na-22, Cs-137, Co-60, Mn-54, Cd-109, Ba-133 and an unknown mixture of two nuclides."

and between us and the donor, we came up with the idea to do research that would add valuable data to all those working on replications. For a start we want to see

1. how far these samples emissions would be attenuated by the kind of reactor materials we are using

2. if they can get through, would they trigger a reaction?

The first would help people understand the reality of what should be being seen outside a reactor should there be high energy photons being generated inside.

The second is worth considering because Alexander Parkhomov has at least 2 Strontium 90 sources in his neutrino experiment that is under 1 meter away from the Ni+LiAlH4 experiments he is conducting. 90 Sr is a know beta emitter, beta emission has been claimed as one way to form Rydberg state Hydrogen. It is likely though that none of these emissions reach the reactor.

Bob Higgins has his own personal UCS20 system which is part of his {GarbageCan} apparatus and has already started the research, with interesting results, see the attached graph.

Alan Goldwater's setup of the UCS30

Alan Goldwater's setup of the UCS30

"Here are some outputs from the measurement of the alumina substrates using the two primary gamma lines of the 241Am source. The source is a point emitter from a smoke detector. The two lines are at 26 keV and 59 keV. The measurements were made as the sum of counts within a ~10% bandwidth for each line. Using a band of channels gave a lot more counts and reduced the uncertainty in each measurement over what it would have been for just a single channel. The integration time was 100 seconds for each sample.

The substrates used are 99.8% alumina that are 2.5" square and ~0.025" thick. 0 to 8 substrates were placed in a stack between the source and the detector. The mass density of each substrate was measured and the plot is attenuation vs. mass density. However, the greatest mass density data point corresponds to 8 substrates which is 0.2" of alumina (a lot of alumina).

As can be seen in the plot, even the 26 keV photons penetrate the 0.2" thick alumina with relatively high efficiency (~68%). That's good news. It means that 1) substantial low energy (26 keV) photons can make it through the alumina, and 2) the NaI detector can detect them pretty well even at 26 keV.

A linear trend-line was used in this plot, which is not the correct curve for such a transmission analysis. However, the actual curve will differ little from the linear curve over this small attenuation."