|TILT||double||0.0||rotation about longitudinal axis|
|B2||double||0.0||Sextupole term: By=Bo*(1+b2*x2)|
|TIME_OFFSET||double||0.0||time offset of waveform|
||is waveform periodic?|
||phase reference number (to link with other time-dependent elements)|
||pass number to fire on|
||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|
|DEFLECTION_MAP||STRING||NULL||optional filename giving the spatial variation of the deflection|
|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,
. Hence, if the waveform file has the maximum amplitude at
, the beam will get kicked at the peak of the waveform. If the waveform
peaks at , then setting
TIME_OFFSET equal to
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.
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
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
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
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.