On Thu, 2010-10-14 at 23:31 +0200, Tim Gruene wrote: > I would like to understand how the notion of a photon being scattered > from all > electrons in the crystal lattice explains the observation that > radiation damage > is localised to the size of the beam so that we can move the crystal > along and > shoot a different location. >
It's because the probability of this photon choosing the particular path that is outside the beam is low. It is not against the law for a photon to go through collimator material without interacting with it and then hitting crystal outside the beam spot, it's just very unlikely. -- "I'd jump in myself, if I weren't so good at whistling." Julian, King of Lemurs