13.24 CWAKE—A single-pass wake combining longitudinal monopole, transverse dipole, transverse quadrupole, and transverse position-independent (constant) deflecting channels read from one SDDS file. Equivalent to a co-located WAKE and one or more TRWAKE elements, but performs particle binning and bunch assignment only once.

A single-pass wake combining longitudinal monopole, transverse dipole, transverse quadrupole, and transverse position-independent (constant) deflecting channels read from one SDDS file. Equivalent to a co-located WAKE and one or more TRWAKE elements, but performs particle binning and bunch assignment only once.
Parallel capable? : yes
GPU capable? : no
Back-tracking capable? : yes
Spin-tracking capable? : no






Parameter NameUnitsType Default

Description






INPUTFILE STRINGNULL

SDDS file containing the wake functions






TCOLUMN STRINGNULL

column in INPUTFILE giving the wake-function time abscissa






WZCOLUMN STRINGNULL

column in INPUTFILE giving the longitudinal monopole wake Wbzn(t)






WXCOLUMN STRINGNULL

column in INPUTFILE giving the horizontal dipole wake Wbxn(t)






WYCOLUMN STRINGNULL

column in INPUTFILE giving the vertical dipole wake Wbyn(t)






QXCOLUMN STRINGNULL

column in INPUTFILE giving the horizontal quadrupole wake Qbxn(t)






QYCOLUMN STRINGNULL

column in INPUTFILE giving the vertical quadrupole wake Qbyn(t)






CXCOLUMN STRINGNULL

column in INPUTFILE giving the horizontal constant (position-independent) deflecting wake Cbxn(t)






CYCOLUMN STRINGNULL

column in INPUTFILE giving the vertical constant (position-independent) deflecting wake Cbyn(t)






FACTOR double 1

global scale factor applied to every wake channel






ZFACTOR double 1

extra scale factor for the longitudinal channel






XFACTOR double 1

extra scale factor for the horizontal dipole channel






YFACTOR double 1

extra scale factor for the vertical dipole channel






CWAKE continued

A single-pass wake combining longitudinal monopole, transverse dipole, transverse quadrupole, and transverse position-independent (constant) deflecting channels read from one SDDS file. Equivalent to a co-located WAKE and one or more TRWAKE elements, but performs particle binning and bunch assignment only once.






Parameter Name UnitsType Default

Description






QXFACTOR double1

extra scale factor for the horizontal quadrupole channel






QYFACTOR double1

extra scale factor for the vertical quadrupole channel






CXFACTOR double1

extra scale factor for the horizontal constant deflecting channel






CYFACTOR double1

extra scale factor for the vertical constant deflecting channel






N_BINS long 0

number of bins for current histograms (0 for autoscale from beam length and wake dt)






INTERPOLATE long 0

interpolate wake voltage to particle time?






SMOOTHING long 0

Use Savitzky-Golay filter to smooth driver histograms?






SG_HALFWIDTH long 4

Savitzky-Golay filter half-width for smoothing






SG_ORDER long 1

Savitzky-Golay filter order for smoothing






DX M double0.0

x misalignment (applied to transverse driver coordinates)






DY M double0.0

y misalignment (applied to transverse driver coordinates)






TILT RADdouble0.0

rotation about the longitudinal axis






CHANGE_P0 long 0

rematch central momentum after the longitudinal channel applies its kick?






ALLOW_LONG_BEAM long 0

allow beam longer than the wake-function data?






CWAKE continued

A single-pass wake combining longitudinal monopole, transverse dipole, transverse quadrupole, and transverse position-independent (constant) deflecting channels read from one SDDS file. Equivalent to a co-located WAKE and one or more TRWAKE elements, but performs particle binning and bunch assignment only once.






Parameter Name UnitsType Default

Description






ACAUSAL_ALLOWED long 0

If non-zero, allow a wake function whose first sample is at t<0 (must include t=0).






RAMP_PASSES long 0

number of passes over which to linearly ramp up the wake to full strength






BUNCHED_BEAM_MODE long 1

if non-zero, then do calculations bunch-by-bunch






START_BUNCH long -1

in bunched beam mode, if non-negative, starting bunch index for computation






END_BUNCH long -1

in bunched beam mode, if non-negative, ending bunch index for computation






GROUP stringNULL

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






The CWAKE element combines the physics of a co-located WAKE (longitudinal monopole), one or more TRWAKE elements (transverse dipole and quadrupole), and two optional position-independent (“constant”) transverse deflecting channels, into a single element. All channels are driven from one SDDS file; particle binning, bunch identification, and the per-bunch loop are done only once across every enabled channel. This typically reduces the per-call overhead by about a factor of two relative to stacking WAKE and one or more TRWAKE elements at the same location.