Polarization parameters

FLUKA team, @ceruttif
I am looking for some clarification on the variables used to defined polarization. The manual says the first 3 parameters of the card can be overridden in the source routine by UBMPOL, VBMPOL,WBMPOL . However, these parameters in source.f appear to be defined as TX(YZ)POL(NPFLKA).
With a quick check, they appear to be the same when used with LPPERP.

Are they?

Thanks
sunil

Dear Sunil,

the UBMPOL, VBMPOL and WBMPOL variables store the polarization values set on the POLARIZA card.

If no POLARIZA card is used the they are initialized to the expected (-2, 0, 0) values.

The TX(Y,Z)POL (NPFLKA) are used to store the polarization values of a single particle in the stack.
If you want to keep the values set on the POLARIZA card in the source routine as well, you can use:

TXPOL (NPFLKA) = UBMPOL
TYPOL (NPFLKA) = VBMPOL
TZPOL (NPFLKA) = WBMPOL

Note: The other polarization characteristics defined on the POLARIZA card are not inherited by the source routine. Those need to be added by the user.

Cheers,
David