10.67 MBUMPER—A time-dependent multipole kicker magnet. The waveform is in SDDS format, with time in seconds and amplitude normalized to 1.

A time-dependent multipole kicker magnet. The waveform is in SDDS format, with time in seconds and amplitude normalized to 1.
Parallel capable? : yes
GPU capable? : no
Back-tracking capable? : no

Parameter Name UnitsType Default


L M double 0.0


STRENGTH double 0.0

geometric strength in 1/mˆ(

TILT RADdouble 0.0

rotation about longitudinal axis

DX M double 0.0


DY M double 0.0


DZ M double 0.0


TIME_OFFSET S double 0.0

time offset of waveform

ORDER long 0

multipole order, where 1 is quadrupole, 2 is sextupole, etc.


is waveform periodic?


phase reference number (to link with other time-dependent elements)


pass number to fire on

N_KICKS long 0

Number of kicks to use for simulation.


<filename>=<x>+<y> form specification of input file giving kick factor vs time


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 multipole kicker magnet. To use this element, you must supply an SDDS file giving the time-dependent waveform. The element is called MBUMPER 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 = tpeak, then setting TIME_OFFSET equal to -tpeak 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. Note that teh first pass is 0, not 1.

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 quadrupole or higher order kicker only. For dipole kickers, see the BUMPER element.

Explanation of <filename>=<x>+<y> format: Several elements in elegant make use of data from external files to provide input waveforms. The external files are SDDS files, which may have many columns. In order to provide a convenient way to specify both the filename and the columns to use, we frequently employ <filename>=<x>+<y> format for the parameter value. For example, if the parameter value is waveform.sdds=t+A, then it means that columns t and A will be taken from file waveform.sdds. The first column is always the independent variable (e.g., time, position, or frequency), while the second column is the dependent quantity.