CFQED

  Constant-Field QED, i.e., the beamstrahlung and coherent pair creation. Both the effects of the beam field and the external field are included. The angular distribution of the final particles is not included.

When the polarization flag (see below) is on, all the polarization effects (longitudinal and transverse spin of electron/positron and linear and circular polarization of photon) are included. CFQED BEAMSTRAHLUNGPAIRCREATION[,] [POLARIZATION,] [PMAX=,] [WENHANCE=,] ;

BEAMSTRAHLUNGPAIRCREATION

   Specifies which parameters to define here. Only one of these may be specified by one CFQED command.

POLARIZATION

Flag to take into account all the polarization effect. (default=No). Note that the flag SPIN (FLAG command) must also be on for polarization calculation.

Maximum probability of events per one time step. (Default=0.1). When the probability exceeds , CAIN stops with a message.

Enhancement factor of radiation rate. . When (default), macro-photons are created such that
When (<1), macro-photons are created more (less) by the factor , each having less (more) weight. When , no photon is created (but the recoil of electron is taken into account.) This operand is introduced in order to avoid poor statistics due to too less macro-photons or memory overflow due to too many macro-photons.

See Sec.5.8 and Sec.5.9 for the formulas and algorithm and for more detail on the enhancement factor.