BUMPER

A time-dependent uniform-field rectangular kicker magnet with no fringe effects. The waveform is in SDDS format, with time in seconds and amplitude normalized to 1.
Parallel capable? : yes

Parameter Name	Units	Type	Default	Description
L	$M$	double	0.0	length
ANGLE	$RAD$	double	0.0	kick angle
TILT	$RAD$	double	0.0	rotation about longitudinal axis
DX	$M$	double	0.0	misalignment
DY	$M$	double	0.0	misalignment
DZ	$M$	double	0.0	misalignment
B2	$1/M^2$	double	0.0	Sextupole term: By=Bo*(1+b2*x2)
TIME_OFFSET	$S$	double	0.0	time offset of waveform
PERIODIC		long	0	is waveform periodic?
PHASE_REFERENCE		long	0	phase reference number (to link with other time-dependent elements)
FIRE_ON_PASS		long	0	pass number to fire on
N_KICKS		long	0	Number of kicks to use for simulation. 0 uses an exact result but ignores b2.
WAVEFORM		STRING	NULL	$<$filename$>$=$<$x$>$+$<$y$>$ form specification of input file giving kick factor vs time
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 simulates a time-dependent kicker magnet as a rectangular dipole with no fringe field effects. To use this element, you must supply an SDDS file giving the time-dependent waveform. The element is called BUMPER to because HKICK, VKICK, KICKER are used for steering magnets.

The arrival time of the beam is taken to define the reference time, $t=0$. Hence, if the waveform file has the maximum amplitude at $t=0$, the beam will get kicked at the peak of the waveform. If the waveform peaks at $t=t_{peak}$, then setting TIME_OFFSET equal to $-t_{peak}$ will ensure that the beam is kicked at the peak amplitude.

By default, the kicker fires on the first beam passage. However, if FIRE_ON_PASS is used, then the kicker is treated like a drift space until the specified pass.

If PHASE_REFERENCE is non-zero, then the initial timing is taken from the first time-dependent element that has the same PHASE_REFERENCE value. This would allow, for example, simulating several kickers firing at the same time. Delays relative to this reference time can then be given with positive adjustments to TIME_OFFSET.

The input file need not have equispaced points in time. However, the time values should increase monotonically.

This element simulates a dipole kicker only. For multipole kickers, see the MBUMPER element.