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LASERQED
COMPTONBREITWHEELER[,]
NPH=,
[NY=,] [NXI=,]
[NLAMBDA=,]
[NQ=,]
XIMAX=,
LAMBDAMAX=,
ETAMAX=,
[PMAX=,]
[ENHANCEFUNCTION=,] ;
- COMPTONBREITWHEELER
-
Specifies which parameters to define here.
-
- Maximum number of laser photons to be
absorbed in one process.
If <0, turn off Compton or Breit-Wheeler.
If =0, use linear Compton/Breit-Wheeler formula.
If , use nonlinear formula.
Note that and are
different. The former is the limit of ,
which contains term only, where as
the latter is a truncation of the
exact series with respect to .
When , none of the following variables
are needed.
When , only longitudinal polarization
is considered and the lasers must be circularly
polarized by 100% (i.e., , ).
-
- Number of abscissa for final energy. Default=20.
-
- Number of abscissa for parameter. Default=20.
-
- Number of abscissa for parameter.
Applies to Compton case only. Default=20.
-
- Number of abscissa for q parameter.
Applies tp Breit-Wheeler case only. Default=50.
-
- Maximum value of for the table.
-
- Maximum value of for the table.
Applies to Compton case only.
-
- Maximum value of for the table.
Applies to Breit-Wheeler case only.
-
- Maximum probability of events per one time
step. If the computed probability exceeds
, CAIN of present version stops with a message.
-
- Defines a function in order to
enhance a part of spectrum.
It is defined
as an expression containing Y as the
final energy parameter (Y).
Its value must be for Y.
Generally speaking, Y close to 1
generates low energy charged particles.
For example,
E NH=1+Step(Y-0.8)*(Y-0.8)*10
will enhance the events with Y>0.8 by a factor
upto 3 (at Y=1).
In the program, the real spectrum function is
multiplied by and, when an event is
generated, the created particles are asigned a weight
.
Note that slightly larger than 1 is useless
(even harmful) because a small fraction
of the parent particle will remain as a macro-particle,
causing a waste of computing time. In the example
above, exactly for Y<0.8.
This function is used only during the initialization
by LASERQED command. Therefore, if the expression
contains user-defined parameters, their values
at the time of LASERQED command are used.
Changing them afterwards will not affect the
computation.
See Sec.5.7.3 and Appendix.A for more detail
Next: CFQED
Up: Commands
Previous: LASER
Toshiaki Tauchi
Thu Dec 3 17:27:26 JST 1998