Define the parameters for the calculation of beam-beam
Note that the longitudinal mesh size,
which is common to beam-beam
field and luminosity calculations, has to be defined by the
by the SET command. Its value at the time
when PUSH started is used thoughout the
- Horizontal width of the mesh in meters
for right and left-going beams.
If is not specified,
is adopted. No default for .
- If WXMAX is given, the with of
the mesh region
can vary in the range when the beam
fraction outside the range defined by WX
and R is significant. Note .
- Aspect ratio ()/()
of the horizontal to vertical mesh size.
This is common to right and left-going beams.
- Number of horizontal and vertical bins.
Present version uses Fast Fourier Transformation
so that a power of 2 is the best choice. Other
numbers are also allowed but those of the form
or or are
- Macro-particle size in units of the bin size.
Macro-particles are treated as a rectangular
of uniform distribution.
Must be . Default=1.
- For (x,y) points outside the mesh region,
a harmonic expansion using the elliptic coordinate
is used. The parameter specifies the
truncation of harmonics. takes only
the total charge term and ignores
the field outside. Default=10.
Note that the particles outside mesh region
receive the beam-beam kick unless ,
but the field created by them is not taken into
account. See Sec.5.6 for more detail.
Thu Dec 3 17:27:26 JST 1998