description: Increases the number of particles in a particle input file by successively
doubling the number. Intended to be used to increase the number of particles produced by a
photoinjector simulation to improve stability of CSR and LSC simulations.
The algorithm is as follows:
For each doubling, insert a new particle “near” every pair of existing particles in time.
The particle has a new t value, but the same (x, xp, y, yp, p) as one of the original
Bin the beam according to t into a large number of bins. Randomize the assignment of
p values relative to other coordinates across particles in the same bin, while additionally
adding a small random value to each p value.
doubleDist6 -input name -output name -doublings number -nt bins
input — A particle distribution file, such as might be used with sdds_beam.
output — A particle distribution file, such as might be used with sdds_beam.
-doublings n — The number of times to double the size of the distribution. The number
of particles in the output file is 2n times the number in the input file.
-nt bins — The number of time bins to use for momentum randomization. This helps
to avoid having many particles with exactly same momentum.