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A map of Bx and By vs x and y.
Parallel capable? : yes
Parameter Name Units Type Default Description
L $M$ double 0.0 length
STRENGTH $NULL$ double 0.0 factor by which to multiply field
ACCURACY $NULL$ double 0.0 integration accuracy
METHOD $NULL$ STRING NULL integration method (runge-kutta, bulirsch-stoer, modified-midpoint, two-pass modified-midpoint, leap-frog, non-adaptive runge-kutta
FILENAME $NULL$ STRING NULL name of file containing columns (x, y, Fx, Fy) giving normalized field (Fx, Fy) vs (x, y)
FX $NULL$ STRING NULL rpn expression for Fx in terms of x and y
FY $NULL$ STRING NULL rpn expression for Fy in terms of x and y
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 transport through a transverse magnetic field specified as a field map. It does this by simply integrating the Lorentz force equation in cartesian coordinates. It does not incorporate changes in the design trajectory resulting from the fields. I.e., if you input a dipole field, it is interpreted as a steering element.

The field map file is an SDDS file with the following columns:

The field map file must contain a rectangular grid of points, equispaced (separately) in x and y. There should be no missing values in the grid (this is not checked by elegant). In addition, the x values must vary fastest as the values are accessed in row order. To ensure that this is the case, use the following command on the field file:

sddssort fieldFile -column=y,incr -column=x,incr

next up previous
Next: BUMPER Up: Element Dictionary Previous: ALPH
Robert Soliday 2014-06-26