Xray - what physics discipline?

[Vector_Joe]

Hi,

New here. I work in the design and manufacture of medical xray tubes (CT applications mostly). So off and on I think about going back to grad school (have a BS in physics-general).

So for my first question to the forum, what discipline would you categorize the field of xray generation. Specifically using a vacuum enclosure, anode, cathode, electron beam, bremmstrahlung and KShell emission?

I'm starting to lean toward quantum physics, but could also see accelerator physics... not sure.

Thanks

Joe