Adds on-axis field data to the simulation. The user must provide an SDDS file giving . This data is used to compute , , and using an off-axis expansion in and assuming and .
Any number of
add_on_axis_fields commands may be given.
&add_on_axis_fields filename = fieldProfile.sdds, z_name = z, Ez_name = Ez, Ez_peak = 30e6, phase = 180, expansion_order = 2 fields_used = fieldUsed.sdds, &end
This command loads on-axis field data from columns
fieldProfile.sdds, and scales it so that the peak
field is 30 MV/m. The phase, , is set to 180 degrees. Because
spiffe simulates electrons, if is positive, the phase
factor must be negative to provide acceleration. I.e.,
is the accelerating phase.
#namelist add_on_axis_fields STRING filename = NULL; STRING z_name = NULL; STRING Ez_name = NULL; double Ez_peak = 0; double frequency = 0; double z_offset = 0; long expansion_order = 3; STRING fields_used = NULL; #end