Thermal neutron detection using boron-10 and sodium
salicylate doped epoxy Films
by Hayn Park
Theses on thermal neutron detector construction
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- Joined: Thu Jun 28, 2001 1:30 am
- Real name: Jon Rosenstiel
- Location: Southern California
Theses on thermal neutron detector construction
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- Carl Willis
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Re: Theses on thermal neutron detector construction
That's a neat article Jon.
Actually a bit of work has been done on lithium salicylate as a neutron detecting material. Salicylic acid and its salts are reported to be charged-particle scintillators that function even in aqueous solution, and of course the Li-6 furnishes the required particles on neutron capture. I wish I could upload the articles I have, but they are "hard copy."
Lithium-6 is not too expensive and can be bought commercially. The papers I have describe how it is dissolved in methanol to form an alkoxide, which is subsequently neutralized with dry salicylic acid to form the neutron-detecting medium. I have the materials, minus that critical Li-6, to try it out. Maybe later this semester.
Unfortunately, this guy did not really get any characteristic pulse-height spectra showing a clear neutron peak (he'd expect to see a distinct peak from the nearly constant energy of the (n, a) products). This is probably because of the opacity of his scintillators, owing to the hydrophilic lithium and sodium salts not being substantially soluble in the hydrophobic epoxy base. Also these materials tend to attract water itself.
Real neat project.
-Carl
Actually a bit of work has been done on lithium salicylate as a neutron detecting material. Salicylic acid and its salts are reported to be charged-particle scintillators that function even in aqueous solution, and of course the Li-6 furnishes the required particles on neutron capture. I wish I could upload the articles I have, but they are "hard copy."
Lithium-6 is not too expensive and can be bought commercially. The papers I have describe how it is dissolved in methanol to form an alkoxide, which is subsequently neutralized with dry salicylic acid to form the neutron-detecting medium. I have the materials, minus that critical Li-6, to try it out. Maybe later this semester.
Unfortunately, this guy did not really get any characteristic pulse-height spectra showing a clear neutron peak (he'd expect to see a distinct peak from the nearly constant energy of the (n, a) products). This is probably because of the opacity of his scintillators, owing to the hydrophilic lithium and sodium salts not being substantially soluble in the hydrophobic epoxy base. Also these materials tend to attract water itself.
Real neat project.
-Carl
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Re: Theses on thermal neutron detector construction
This thesis was mentioned in the radiation dectection section back in November - I'm glad somebody else picked up on it. I did a little research at the time, and B10-enriched boric acid seems to be fairly readily available. As I recall, this is one of the compounds that dissloved in the epoxy and stayed clear. One could start with ordinary boric acid and probably get acceptable results, due to the relatively high density of boron compared to a gaseous BF3 detector. I'd want to experiment with the ordinary boric acid first any way to get the proportions right, as the enriched boric acid is likely to be too expensive to afford mistakes.