If we could irradiate a metal or a plasma with a coherent beam of hard X-rays, would the main effect be an ordered oscillation of the electrons like with a classical EM wave, or "compton-style" collisions?
For example, When copper metal is irradiated with X-rays, some X-rays penetrate into metal and get absorbed. If the metal is thin, some X-rays come out from the other side with low intensity.
If the incident X-ray beam is at an angle to copper block, scattered X-rays can be detected. Depending upon angle of incidence, some back scattered X-rays are also expected.
Interestingly, if the incident X-ray energy is of higher energy than K X-ray energy of copper, characteristic Cu X-rays are emitted from copper block along with back scattered X-rays.