CORGPIPE

A corrugated round pipe, commonly used as a dechirper in linacs.
Parallel capable? : yes

Parameter Name	Units	Type	Default	Description
L	$M$	double	0.0	length
RADIUS	$M$	double	0.0	pipe radius
PERIOD	$M$	double	0.0	period of corrugations ($<$$<$ radius recommended)
GAP	$M$	double	0.0	gap in corrugations ($<$ period required)
DEPTH	$M$	double	0.0	depth of corrugations ($<$$<$ radius, $>$  period recommended)
DT	$S$	double	0.0	maximum time duration of wake (0 for autoscale)
TMAX	$S$	double	0.0	maximum time duration of wake (0 for autoscale)
N_BINS		long	0	number of bins for charge histogram (0 for autoscale)
INTERPOLATE		long	0	interpolate wake?
SMOOTHING		long	0	Use Savitzky-Golay filter to smooth current histogram?
SG_HALFWIDTH		long	4	Savitzky-Golay filter half-width for smoothing
SG_ORDER		long	1	Savitzky-Golay filter order for smoothing
CHANGE_P0		long	0	change central momentum?
ALLOW_LONG_BEAM		long	0	allow beam longer than wake data?
RAMP_PASSES		long	0	Number of passes over which to linearly ramp up the wake to full strength.
GROUP		string	NULL	Optionally used to assign an element to a group, with a user-defined name. Group names will appear in the parameter output file in the column ElementGroup

This element implements the longitudinal wake for a corrugated pipe using a model by K. Bane [38]. The method used is identical to that for the WAKE element. The only difference is that instead of providing a file to specify the wake, one specifies the parameters of Bane's model, as described above.

Setting the N_BINS and TMAX paramaters to 0 is recommended. This results in auto-scaling of the number of bins and the time spacing of the wake to ensure sufficient length to cover the beam and a sufficiently fine time step to resolve the oscillations in the wake.

As with WAKE, the default degree of smoothing (SG_HALFWIDTH=4) may be excessive. It is suggested that users vary this parameter to verify that results are reliable if smoothing is employed (SMOOTHING=1).