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Next: VKICK Up: Element Dictionary Previous: TWPL


An undulator kick map (e.g., using data from RADIA).
Parallel capable? : yes
Parameter Name Units Type Default Description
L $M$ double 0.0 length
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
FIELD_FACTOR   double 1 Factor by which to multiply the magnetic fields.
XY_FACTOR   double 1 Factor by which to multiply the x and y values in the input file.
INPUT_FILE   STRING NULL Name of SDDS file with undulator kickmap data.
N_KICKS   long 1 Number of kicks into which to split the element.
PERIODS   long 0 Number of periods (for radiation integral computations only).
KREF   double 0.0 Reference value of undulator parameter. K=KREF*FIELD_FACTOR is used for radiation integral calculations only assuming period=L/PERIODS.
SYNCH_RAD   long 0 include classical synchrotron radiation?
ISR   long 0 include incoherent synchrotron radiation (scattering)?
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 provides simulation of undulators using kick maps [27]. A script (km2sdds) is provided with the elegant distribution to translate RADIA [28] output into SDDS for use by elegant.

The input file has the following columns:

The values of x and y must be laid out on a grid of equispaced points. It is assumed that the data is ordered such that x varies fastest. This can be accomplished with the command
% sddssort -column=y,increasing -column=x,increasing input1.sdds input2.sdds
where input1.sdds is the original (unordered) file and input2.sdds is the new file, which would be used with UKICKMAP.

The data file is assumed to result from integration through a full device. If instead one integrates through just a single period of a full device, one must multiply FIELD_FACTOR by $\sqrt{N_u}$, where $N_u$ is the number of periods in the full device. It also makes a certain amount of sense to set N_KICKS equal to $N_u$.

elegant performs radiation integral computations for UKICKMAP and can also include radiation effects in tracking. This feature has limitations, namely, that the radiation integral computations assume the device is horizontally deflecting. However, in tracking, no such assumption is made. N.B.: at present this element is not presently included in beam moments computations via the moments_output command.

This element was requested by W. Guo (BNL), who also assisted with the implementation and debugging.

next up previous
Next: VKICK Up: Element Dictionary Previous: TWPL
Robert Soliday 2014-03-21