Magnetic field expansion in a bent-solenoid channel

摘要

Bent-solenoid channels are being considered for generating dispersions desired for emittance exchange between the transverse and longitudinal motions of a muon beam in a longitudinal ionization cooling channel. Correct field expansion around the reference orbit is important for reliable particle-tracking simulation as well as beam dynamics analysis. This paper reviews the magnetic field expansion for a bent-solenoid channel. In particular, ready-to-use formulas for the magnetic field and its potentials are given.