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RFCW

A combination of RFCA, WAKE, TRWAKE, and LSCDRIFT.
Parallel capable? : yes
Parameter Name Units Type Default Description
L $M$ double 0.0 length
CELL_LENGTH $M$ double 0.0 cell length (used to scale wakes, which are assumed to be given for a cell)
VOLT $V$ double 0.0 voltage
PHASE $DEG$ double 0.0 phase
FREQ $Hz$ double 500000000 frequency
Q   double 0.0 cavity Q (for cavity that charges up to voltage from 0)
PHASE_REFERENCE   long 0 phase reference number (to link with other time-dependent elements)
CHANGE_P0   long 0 does element change central momentum?
CHANGE_T   long 0 see RFCA documentation
FIDUCIAL   STRING NULL mode for determining fiducial arrival time (light, tmean, first, pmaximum)
END1_FOCUS   long 0 include focusing at entrance?
END2_FOCUS   long 0 include focusing at exit?
BODY_FOCUS_MODEL   STRING NULL None (default) or SRS (simplified Rosenzweig/Serafini for standing wave)
N_KICKS   long 0 Number of kicks to use for kick method. Set to zero for matrix method.
ZWAKE   long 1 If zero, longitudinal wake is turned off.
TRWAKE   long 1 If zero, transverse wakes are turned off.
WAKEFILE   STRING NULL name of file containing Green functions
ZWAKEFILE   STRING NULL if WAKEFILE=NULL, optional name of file containing longitudinal Green function

A combination of RFCA, WAKE, TRWAKE, and LSCDRIFT.
Parameter Name Units Type Default Description
TRWAKEFILE   STRING NULL if WAKEFILE=NULL, optional name of file containing transverse Green functions
TCOLUMN   STRING NULL column containing time data
WXCOLUMN   STRING NULL column containing x Green function
WYCOLUMN   STRING NULL column containing y Green function
WZCOLUMN   STRING NULL column containing longitudinal Green function
N_BINS   long 0 number of bins for current histogram
INTERPOLATE   long 0 interpolate wake?
SMOOTHING   long 0 Use Savitzky-Golay filter to smooth current histogram?
SG_HALFWIDTH   long 4 Savitzky-Golay filter half-width for smoothing
SG_ORDER   long 1 Savitzky-Golay filter order for smoothing
DX $M$ double 0.0 misalignment
DY $M$ double 0.0 misalignment
LINEARIZE   long 0 Linearize phase dependence?
LSC   long 0 Include longitudinal space-charge impedance?
LSC_BINS   long 1024 Number of bins for LSC calculations
LSC_INTERPOLATE   long 1 Interpolate computed LSC wake?
LSC_LOW_FREQUENCY_CUTOFF0   double -1 Highest spatial frequency at which low-frequency cutoff filter is zero. If not positive, no low-frequency cutoff filter is applied. Frequency is in units of Nyquist (0.5/binsize).
LSC_LOW_FREQUENCY_CUTOFF1   double -1 Lowest spatial frequency at which low-frequency cutoff filter is 1. If not given, defaults to LOW_FREQUENCY_CUTOFF1.

A combination of RFCA, WAKE, TRWAKE, and LSCDRIFT.
Parameter Name Units Type Default Description
LSC_HIGH_FREQUENCY_CUTOFF0   double -1 Spatial frequency at which smoothing filter begins for LSC. If not positive, no frequency filter smoothing is done. Frequency is in units of Nyquist (0.5/binsize).
LSC_HIGH_FREQUENCY_CUTOFF1   double -1 Spatial frequency at which smoothing filter is 0 for LSC. If not given, defaults to HIGH_FREQUENCY_CUTOFF0.
LSC_RADIUS_FACTOR   double 1.7 LSC radius is (Sx+Sy)/2*RADIUS_FACTOR
WAKES_AT_END   long 0 Do wake kicks at end of segment (for backward compatibility)?
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 is a combination of the RFCA, WAKE, and TRWAKE elements. As such, it provides combined simulation of an rf cavity with longitudinal and transverse wakes, as well as longitudinal space charge.

For the wakes, the input files and their interpretation are identical to WAKE and TRWAKE, except that the transverse and longitudinal wakes are interpreted as the wakes for a single cell of length given by the CELL_LENGTH parameter.

Users should read the entries for WAKE, TRWAKE, and RFCA for more details on this element.

This element simulates longitudinal space charge using the method described in [22]. This is based on the longitudinal space charge impedance per unit length

\begin{displaymath}
Z_{lsc}(k) = \frac{i Z_0}{\pi k r_b^2} \left[ 1 - \frac{kr_b}{\gamma}K_1 \left(\frac{kr_b}{\gamma}\right)\right]
\end{displaymath} (67)


next up previous
Next: RFDF Up: Element Dictionary Previous: RFCA
Robert Soliday 2014-06-26