[G12] electron helicity

[Jason Bono]

Hello all,
 
As i had mentioned at our meeting, before i had to hang up and run for my life, that I'm looking into the sign of the electron helicity. This info was stored in the HEAD bank under EVTCLASS for other experiments .
for example one experiment had:

EVTCLAS= 1,2 or 11 for positive helicity.
and,
EVTCLAS= 4,5 or 14 for negative helicity.

 From a bosdump over various  g12 runs i see that EVTCLASS=14 for the vast majority of the data.  This could mean one of two things:

1)  The true electron helicity is overall negative meaning that g12 did not collect data with a helicity flip rate during production runs (other experiments did with a rate of 30HZ which give net zero helicity, even for polarized experiments)
2) The reliable event by event electron helicity information is actually not stored in the EVTCLASS or the convention is different.

Can anyone verify 1? This would explain why the moller measurements are consistently negative as well.  However it was my understanding that MCC had to flip the helicity. 
if 2, Does anyone know where i can learn about the convention used by g12? All i can see from the CLAS online BOS viewer is that  EVTCLASS=1-15 means "Physics Events".

Any input would be appreciated and if i am not clear please ask me to elaborate.
Regards,
Jason
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