Can Autoradiographs Identify Pu-239 Amidst Other Radioactive Materials?

[divmstr95]

I am officially stumped. I am studying the exposure to personnel from Operation Crossroads (Able and Baker bombs). One of the things I have run across is a claim that Col. Warren Stafford proved there was plutonium in the lagoon because a surgeon fish had autoradiographed a film it was laid on after eating contaminated lagoon algae (the claim is actually from the official photo archive). This was about 9 days after the Baker burst.

What I'm trying to figure out is 1) how you definitively identify Pu-239 from an autoradiograph in an environment where Pu-239, U-235, fission products from both, and activated materials from the environment are all present and 2) how alpha radiation exposes film (the claim also stated that Alpha radiation was responsible for image).

Am I missing something?

Thanks

 

[BigJDubs]

for your question. Unfortunately, it is not possible to definitively identify Pu-239 from an autoradiograph in an environment where Pu-239, U-235, fission products from both, and activated materials from the environment are all present. This is because all of these elements emit different types of radiation, and they each have unique energy spectra that would need to be studied in order to identify them. Additionally, alpha radiation cannot expose film; it is too low-energy to be absorbed by film. The only type of radiation that can expose film is gamma radiation.