Hello,
some days ago I finally computed the equivalent luminosity of our Vub
cocktail MC but I always forgot to mention it during our meetings...here
are the numbers. Ciao, Concezio.
Decay file: BB_BrecoCocktail_Xulnu.dec
In the BrecoCocktail side we simulate the following fraction of D meson
decays (including the BRs of the decay products themselves):
D0: 27.0%
D+: 25.3%
D*0: 100% (->D0 X: 100%)
D*+: 100% (->D0pi+: 68.8%, ->D0pi0: 31.2%)
The amount of the simulated B decays in the four seeds is
B0-> D*+X : 3.25%
B0-> D+X : 2.36%
B+-> D*0X : 4.16%
B+-> D0X : 3.13%
Taking into account the fraction of simulated D(*) meson decays we have:
BR(B0 -> D*+ X, D*+ sx) = 3.25%*[68.8%*27% + 31.2%*25%] = 0.86%
BR(B0 -> D+ X, D+ sx) = 2.36%*25% = 0.6%
Total B0: 1.46%
BR(B+ -> D*0 X, D*0 sx) = 4.16%*27% = 1.12%
BR(B+ -> D0 X, D0 sx) = 3.13%*27% = 0.85%
Total B+: 1.97%
The Vub side decays have BRs of 0.2959% (B0) and 0.2629% (B+).
The effective cross-section is therefore:
0.525 nb * [1.46%*0.2959%+1.97%*0.2629%] ~ 5 *10^-5 nb.
This means that e.g. 10^5 Vub cocktail MC events are equivalent to a
luminosity of
10^5/(5*10^-5) nb-1 = 2*10^9 nb-1 = 2 ab-1.
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