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Generation of particles

This operation generates a set of particles to be used subsequently in one or more particle tracking operations. Presently only gaussian distributions can be generated. This operation MUST ALWAYS be preceded by a BEAM definition operation and by a SEED operation. 

Input format 


GENEration of particles 


nopt $\sigma_{1} \dots \sigma_{6}$ scale npart 

$x_{0},x'_{0},y_{0},y'_{0},al_{0},del_{0}$
Parameter definitions

nopt

1 $\textstyle \parbox{10cm}{ the particles are randomly generated on the surface ... ...e not operational (but for computational efficiency they should be set to 1)}$

3 $\textstyle \parbox{10cm}{ the particles generated have coordinates that satisfy a six dimensional gaussian distribution.}$

$\sigma_{i}$

$\textstyle \parbox{10cm}{ the number of sigmas above which the gaussian distr... ...evious BEAM operation which is assumed to define the one sigma distribution.}$

scale

$\textstyle \parbox{10cm}{ scales the beam size by the given factor.}$

npart

$\textstyle \parbox{10cm}{ number of particles to be generated. Maximum number mxpart (initially set at 1000 or 10000 depending on versions)}$

$x_{0},x'_{0},y_{0},y'_{0},al_{0},del_{0}$

$\textstyle \parbox{10cm}{ centroid coordinates around which the beam is generated.}$



Examples

The example shown is taken from dem07 . It will generate 500 particles inside the ellipsoid defined by a previous beam matrix definition using a gaussian distribution truncated at 6 sigmas for the transverse coordinates and 1 sigma for the longitudinal coordinates. 

GENERATION OF PARTICLES
3 6 6 6 6 1 1 1.0 500
0 0 0 0 0 0,


Dobrin Kaltchev 2004-10-20