Setup of a modern Compton scattering experiment. The radioactive sample is shielded inside a stack of lead bricks with a small pinhole through which particles can escape impacting the target (a scintillation counter) which scatters the particles.
<a href="//commons.wikimedia.org/wiki/User:Changlc" title="User:Changlc">L. Chang</a>
<span class="int-own-work" lang="en">Own work</span>