1. CMSSW_3_1_1 preproduction samples
/ppMuX/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
/ppMuXLoose/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
/BtoJPsiMuMu/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
/JPsiMuMu/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
/Upsilon1S/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
/JPsiEE/Summer09-MC_31X_V2_preproduction_311-v1/GEN-SIM-RECO
Preproduction samples, use them and test your codes.
17, July, 2009
Zheng Wang

2. For B physics analyses:
A “B Physics Analysis Software “ have been created:
In which:
MC generation and detector simulation
Analysis software
Tutorials
Validation
Useful liks
17, July, 2009
Zheng Wang

3. Validation of a fit
17, July, 2009
Zheng Wang

4. Validation of a Fit
The Validation of a fit: The fit result is no bias; The fitting error consistent with the probability of statistics(一致性，无偏性，有效性）.
Input/output test: Fits on as larger as controlled samples （toy MC samples, or separated real data samples) to test input/output mean values and fitting errors.--if found the bias is ab, take “a” as correction and “b” as the sys. error.
17, July, 2009
Zheng Wang

5. Mean/error tests of a fit (1)
Mean test: compare the difference between the input values and fitting result.
A fit: 1000 MC samples, in which nsignal= 100, nbg=200
17, July, 2009
Zheng Wang

6. Mean/error tests of a fit (2)
Error test: “Pull” distribution
If the fit is no-bias, the mean value of pull distribution is zero; If the fitting error is “good”, the sigma of “pull” is 1; That means the “pull” should be a N(0,1) distribution.
Nfitsig : Fitted signal number for i MC sample.
Ntruthsig: The MC truth signal number of i MC sample (by MC truth matching, R cut)
fit: event fitting error
17, July, 2009
Zheng Wang

7. “Pull” distribution Pull(Nsig)
1> “Pull” test do not verify which fits are the better, it is only prove the validation of the fit.
2>For the low statistics signal, event number distribution is not normal distribution, but possion distribution. “Pull” test will not be a N(0,1) distribution.
Pull(Nsig)
Pull(Nsig)
17, July, 2009
Zheng Wang

8. Fits in B->J/ analysis
Combined prompt J/ and b->J/X samples (10pb-1); pass the same trigger path and selection criteria as those at large sample (43.5pb-1).
7 pTbins, 1-D binned maximum likehood fit over inv. Mass of  track.
Signal PDF: obtained from B mass shape from 43.5pb-1 data, (histogram fit).
Bkg PDF: exponential floating the slope.
Fit over the range GeV.
17, July, 2009
Zheng Wang

9. Fit in B->J/K in each bin
17, July, 2009
Zheng Wang

10. Pull test Mean:0.0239.320 Sigma:1.22  0.08 Mean:-0.4140.252
17, July, 2009
Zheng Wang