- type: action/setup command.
- function: compute frequency map from tracking and use it to determine the chromatic and
amplitude tune footprints.
- sequence: must follow run_control.
- can use parallel resources (Pelegant)
- N.B.: the number of turns tracked is set by the run_control command.
- Command syntax, including use of equations and subcommands, is discussed in 7.2.
STRING delta_output = NULL,
STRING xy_output = NULL,
double xmin = -0.02,
double xmax = 0.02,
double ymin = 1e-6,
double ymax = 0.02,
double x_for_delta = 1e-6,
double y_for_delta = 1e-6,
double delta_min = 0,
double delta_max = 0,
long ndelta = 21,
long separate_xy_for_delta = 0;
long nx = 20,
long ny = 21,
long verbosity = 1,
long quadratic_spacing = 1,
long compute_diffusion = 1;
long diffusion_rate_limit = -5,
long immediate = 0
long filtered_output = 1;
long ignore_half_integer = 0;
This command makes available the following quantities for optimization. All quantities are limited
by particle survival, crossing of integer and half-integer resonances, and the diffusion rate
- FP.nuxSpreadChrom,FP.nuySpreadChrom — Spread in tunes due to chromaticity.
- FP.nuxChromMin, FP.nuxChromMax, FP.nuyChromMin, FP.nuyChromMax — Minimum and
maximum values of the x and y tunes from chromatic tune footprint.
- FP.deltaLimit — Minimum of absolute values of positive and negative δ limits.
- FP.nuxSpreadAmp, FP.nuySpreadAmp — Spread in tunes due to amplitude.
- FP.nuxAmpMin, FP.nuxAmpMax, FP.nuyAmpMin, FP.nuyAmpMax — Minimum and maximum
values of the x and y tunes from amplitude tune footprint.
- FP.xSpread, FP.ySpread — Spread in x and y values.
- FP.xyArea — Area of the limited x-y region, comparable to a dynamic acceptance. However,
this area is determined from a fixed grid and is not suitabl to optimization by itself.
- FP.diffusionRateMaxChrom, FP.diffusionRateMaxAmp — Maximum diffusion rates in
chromatic and amplitude scans.
Typically, one strives to minimize FP.nuxSpreadChrom,FP.nuySpreadChrom, FP.nuxSpreadAmp,
FP.nuySpreadAmp, FP.diffusionRateMaxChrom, and/or FP.diffusionRateMaxAmp while maximizing
FP.deltaLimit, FP.xSpread, and/or FP.ySpread, and ensuring that FP.xyArea, at minimum, doesn’t
decrease. I.e., one wants the maximum stable region for momentum and position deviations with the
minimum spread in tunes and minimum diffusion.