link to lecture transcript - UT-H GSBS Medical Physics Class Site
link to lecture transcript - UT-H GSBS Medical Physics Class Site
link to lecture transcript - UT-H GSBS Medical Physics Class Site
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Now we also look at the graph and see that dσ/dE is approximately constant with a<br />
value of 40 10 -30 m 2 /e MeV.<br />
To a first approximation, let’s forget about the Comp<strong>to</strong>n edge; we will just<br />
approximate the integration by assuming that dσ/dE is constant. To do the<br />
integration, we multiply dσ/dE by the energy interval, 0.606 MeV, and find that σ is<br />
the value of 24 10 -30 m 2 /e. Now if we look at the number in Johns & Cunningham<br />
we find it’s 23.5 10 -30 m 2 /e. So simply by assuming dσ/dE <strong>to</strong> be constant, we get<br />
a very good estimate of the <strong>to</strong>tal cross section.<br />
29
Change language