Channels

Seven wake channels are supported; each is enabled by naming its column in the input SDDS file. Channels whose column is left at the default (NULL) are disabled. At least one channel must be enabled.






channel drive (dx,dy)probe (px,py)kick oncolumn param





longitudinal (0,0) (0,0) ΔE WZCOLUMN
x dipole (1,0) (0,0) ΔxWXCOLUMN
y dipole (0,1) (0,0) ΔyWYCOLUMN
x quadrupole(0,0) (1,0) ΔxQXCOLUMN
y quadrupole(0,0) (0,1) ΔyQYCOLUMN
x constant (0,0) (0,0) ΔxCXCOLUMN
y constant (0,0) (0,0) ΔyCYCOLUMN





The two constant channels apply a uniform transverse deflection that depends only on the bunch current I(t), not on the centroid position of the bunch or the position of the probe particle. These model deflecting wakes from asymmetric structures where the wake voltage is independent of the probe particle’s transverse coordinates.

Five of the channels (longitudinal, x/y quadrupole, x/y constant) share the same I(t) driver histogram; this histogram is built exactly once per bunch regardless of how many of those channels are enabled. Each transverse-dipole channel adds one additional moment histogram (xI(t) or yI(t)).