Re: GEANT Branching Fraction Table

[Eugene Chudakov <gen@jlab.org>]

Matt,

the decay map is initialized in a GEANT routine GPART (gpart.F)
by calling a routine GSDK (gsdk.F) for each particle.
You may redefine this, by calling GSKD again, with different call-parameters.
Eta has a number 17 in GEANT:
   CALL GSDK(17,br(1),mode(1))
The default values are:
branching ratios br: 38.80, 31.90, 23.6,   4.88,  0.5,   0.071
particles/mode mode:   101,70707,70908,10908,10302,10107
 (2 decimal digits per one particle, so 10107 means pi0,gamma,gamma)

Eugene

On Thu, 31 Jul 2008, Matthew Shepherd wrote:

>
> Sascha,
>
> Thanks -- yes, for PYTHIA, just the eta itself is passed onto GEANT.
> Do you know how to override the default decay branching fractions in
> the code?
>
> I see that (unfortunately) GEANT has builtin a non-zero branching
> fraction for eta -> pi^0 gamma gamma which one of the rare signal
> mdoes that Liping is interested in.
>
> -Matt
>
>
> On Jul 31, 2008, at 3:07 PM, Alexander Somov wrote:
>
> >
> > http://wwwasdoc.web.cern.ch/wwwasdoc/geant_html3/node73.html#DRAW001
> > (the same table is in geant 3.21 manual)
> >
> > (I am not sure that your eta decays in geant; it might decay
> > in the event generator directly (?))
> >
> > Sascha
> >
> >
> > On Thu, 31 Jul 2008, Matthew Shepherd wrote:
> >
> >>
> >> Hi,
> >>
> >> Can anyone tell me where the branching fraction table for eta's is
> >> coded into GEANT3?
> >>
> >> Thanks!
> >>
> >> -Matt
> >>
> >>
> >
>
>