I wanted a simple but smooth electromagnetic field model of an RF cavity for use in particle tracking.  I didn't want to design the whole cavity yet, so assumed a particular on-axis field function and then used Maxwell's equations to give a power series in radius.  (I loosely based this on a similar note for magnet fields that I wrote in 2013).
<br /><a href='https://stephenbrooks.org/ap/report/2026-9/rffield.pdf
'>https://stephenbrooks.org/ap/report/2026-9/rffield.pdf
</a><br />#accelerators #physics #electromagnetism