Longitudinal space charge impedance
Parallel capable? : yes
GPU capable? : yes
Backtracking capable? : yes
Parameter Name  Units  Type  Default  Description 
L  M  double  0.0  length 
LEFFECTIVE  M  double  0.0  effective length (used if L=0) 
BINS  long  0  number of bins for current histogram 

SMOOTHING  short  0  Use SavitzkyGolay filter to smooth current histogram? 

SG_HALFWIDTH  short  1  SavitzkyGolay filter halfwidth for smoothing current histogram 

SG_ORDER  short  1  SavitzkyGolay filter order for smoothing current histogram 

INTERPOLATE  short  1  Interpolate wake? 

LSC  short  1  Include longitudinal spacecharge impedance? If zero, acts like ordinary drift. 

AUTO_LEFFECTIVE  short  0  In nonzero and if L=0, the LEFFECTIVE parameter is set to the length of the previous element. 

LOW_FREQUENCY_CUTOFF0  double  1  Highest spatial frequency at which lowfrequency cutoff filter is zero. If not positive, no lowfrequency cutoff filter is applied. Frequency is in units of Nyquist (0.5/binsize). 

LOW_FREQUENCY_CUTOFF1  double  1  Lowest spatial frequency at which lowfrequency cutoff filter is 1. If not given, defaults to LOW_FREQUENCY_CUTOFF1. 

HIGH_FREQUENCY_CUTOFF0  double  1  Spatial frequency at which smoothing filter begins. If not positive, no frequency filter smoothing is done. Frequency is in units of Nyquist (0.5/binsize). 

LSCDRIFT continued
Longitudinal space charge impedance
Parameter Name  Units  Type  Default  Description 
HIGH_FREQUENCY_CUTOFF1  double  1  Spatial frequency at which smoothing filter is 0. If not given, defaults to HIGH_FREQUENCY_CUTOFF0. 

RADIUS_FACTOR  double  1.7  LSC radius is (Sx+Sy)/2*RADIUS_FACTOR 

GROUP  string  NULL  Optionally used to assign an element to a group, with a userdefined name. Group names will appear in the parameter output file in the column ElementGroup 

This element simulates longitudinal space charge in a drift space using the method described in [22]. This is based on the longitudinal space charge impedance per unit length
 (68) 
If L is 0 and LEFFECTIVE is not, then the element provides a LSC kick with impedance given by Z_{lsc}L_{effective}. This can be used to insert an LSC kick that integrates the longitudinal space charge effect of a section of a lattice. This should be used only for cases where there is very little relative longitudinal motion of particles.
Two simple filters are provided.
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LSRMDLTR