Hi Antonio,

for the reduced ntuples, Run1+2 are always merged and it does not seem
that we can distinguish between events from Run1 and Run2 using the run
variable (at least it does not work for the other Runs in generic MC.
Would it be easy enough to split the reduced ntuples for Run1 and Run2,
that way we could use Wolfgang's machinery to do this reweighting...

Cheers,
Kerstin


> Hello vub-recoilers,
>
> I computed weights for the different Runs in MC, so that the relative
> numbers of events match the numbers of BBbar events in data for a given
> Run (I use BbkLumi to get the number of BBbar pairs in data).
>
> Since we are doing this Run-by-Run anyway, I also scale the numbers of
> B+B- and B0B0bar to be consistent between different Runs. For this I use
> the PDG 2006 number: Gamma(Ups(4S)->B+B-)/Gamma(Ups(4S)->B0B0bar)=1.026.
>
> Here are the weights I find:
>
> Generic MC:
>         B0B0bar   B+B-
> Run 1   0.8709    0.9031
> Run 2   0.9272    0.9522
> Run 3   0.9994    1.1003
> Run 4   0.9346    0.9543
> Run 5   1.0000    0.9750
>
> Signal MC:
>         B0B0bar   B+B-
> Run 1   0.9616    0.9866
> Run 2   0.9711    0.9964
> Run 3   0.9746    0.9999
> Run 4   0.9878    1.0135
> Run 5   1.0000    1.0260
>
> More numbers and details can be found here:
> http://costard.lbl.gov/~kerstin/vubunf/ana32/mayprod.txt
>
> We can expand Wolfgang's
> double VirClass::getGenericSPWeight() and
> double VirClass::getSignalSPWeight() to apply these weightings in VVF.
>
> This does not change the magic k number for the signal MC, since the
> weights for 2575 and 6333 are the same.
>
> Happy reweighting,
>
> Kerstin
>
>
>
> Thanks, Roberto, for producing the files to let us count the
> generated signal MC events!
>
>