Showing posts with label Irridator. Show all posts
Showing posts with label Irridator. Show all posts

Monday, July 25, 2011

Neutron Profiles

Some more flux profiles of the irridator.  I think the energy deposition is the coolest; you can see how much energy the cadmium (high neutron absorbance) adsorbs, compared to the air and the Li-6 glass.  You can also clearly see the reduction in the neutron flux as well. Still confused why the neutron flux over the two wells are equivalent when the alpha fluxes are not; the alpha's are produced in (n,alpha) reactions so I would expect there to be a one to one correspondence.






Gamma Flux Profile



You might think that the lead cylinder would attenuate photons more than the cadmium, but this is not so since the attenuation coeffients are about the same:
Source

The sudden changes in the spectrum are from the orbital levels of the electrons - they are label in the original data set.  (Pretty Nifty, huh?).  Note that gamma's follow an exponential decay $$I/I_0 = e^{-(\mu/\rho)x}$$, and I have already multiplied by the density, so it makes sense that there would be a large attenuation for low energy gammas.