RFMULTIPOLE: Thin Radio-Frequency Multipole

Label:  RFMULTIPOLE, VOLT=real, LAG=real,
  HARMON=integer, FREQ=real,
  LRAD=real, TILT=real,
  KNL:={k0nl, k1nl, k2nl, ... },  ! Normal coefficients
  KSL:={k0sl, k1sl, k2sl, ... },  ! Skew coefficients
  PNL:={p0n,  p1n,  p2n,  ... },  ! Normal phases [2pi]
  PSL:={p0s,  p1s,  p2s,  ... };  ! Skew phases [2pi]
    
A RFMULTIPOLE is a thin-lens element which exhibits the properties of an RF-cavity and of a magnet of arbitrary order oscillating the a certain frequency:

	ms: rfmultipole, ksl:={0, 0, 0, k3sl};
Both KNL and KSL may be specified for the same multipole.
A rfmultipole requires the particle energy (ENERGY) and the particle charge (CHARGE) to be set by a BEAM command before any calculations are performed. Notice that, contrary to the regular multipole where the dipole component has no effect on the reference orbit, an RF-Multipole that includes a dipole component bends also the reference orbit.

  Andrea Latina, September 28, 2012