Table of contents:
# Hadron contamination study by using E/p

Studied hadron contamination at high pT. The contamination estimated with Gaussian + exponent fitting doesn't work at high pT.
In the current analysis, it is around 20-30 % at pT > 5 GeV/c. Here we checked whether the contamination is high at high pT.
The method of the study is following

## The E/p distribution with the fitting curve

## Mean position of the distribution as a function of pT

## Sigma of the distribution as a function of pT

## Yields for 1 sigma, 2sigma and 3 sigma cuts of E/p.

## The relative ratios of integrals in the upward vs downward vs total integrals of the signal within the E/p peak

## Summary

# Raw electron comparison

## Compared electron yields between n sigma cut (-3 sigma < E/p < 3 sigma) & fix cut (0.8 < E/p < 1.3)

## Ratio (sigma/fix)

## Comparison E/p fix (0.8-1.3) & 3 sigma yield after efficiency correction

# nSIgma dE/dx efficiency

## nSIgma distribution after applying E/p cut.

## nSIgma efficiency (-1.5 < nSigma < 3.0) from the fitting

## nSigma efficiency (-1.5 < nSigma < 3.0) from some different cuts for eID.

## nSigma efficiency from different variation.

## Summary

# V0 & MC efficiency for EMCal

## Eta dependence

### half E/p (E/p > mean)

#### Efficiency and Raw yields in eta range

#### ratios

### full E/p (0.8 < E/p < 1.3)

#### Efficiency and Raw yields in eta range

#### ratios

### comparison 0.8 <E/p < 1.3 & E/p > mean

#### Comparison 1

#### Comparison 2

efficiency from 0.8 <E/p < 1.3 is scaled by 0.5
### V0 efficiency without E/p cut (Track matching)

### V0 efficiency for E/p cut

### MC efficiency without E/p cut (Track matching)

### MC efficiency for E/p cut

### V0 & MC matching & E/p efficiency comparison (|y|<0.6)

### Summary

## phi dependence

### half E/p (E/p > mean)

#### Efficiency and Raw yields

### full E/p (0.8<E/p <1.3)

#### Efficiency and Raw yields

### comparison 0.8 <E/p < 1.3 & E/p > mean

### Summary

# Track matching comparison

## Distribution

## RMS

# Comparison HFE cross section between V0 correction and MC correction

## V0 vs MC

## Comparison with nSigma TPC half

# Conclusion

- Hadron contamination study by using E/p
- The E/p distribution with the fitting curve
- Mean position of the distribution as a function of pT
- Sigma of the distribution as a function of pT
- Yields for 1 sigma, 2sigma and 3 sigma cuts of E/p.
- The relative ratios of integrals in the upward vs downward vs total integrals of the signal within the E/p peak
- Summary

- Raw electron comparison
- nSIgma dE/dx efficiency
- V0 & MC efficiency for EMCal
- Eta dependence
- phi dependence

- Track matching comparison
- Comparison HFE cross section between V0 correction and MC correction
- Conclusion

- first fit the E/p and find the mean and sigma of the distribution
- Calculate yields
- Up = Integral(m,nXsigma), Dw = Integral(-nXsigma,m), All = Intergal(-nXsigma, nXsigma)
- here n goes from 1 to 3, m is mean of the distribution

- Calculate Up/All and Dw/All
- if the contamination is high Dw/All >> 0.5

- Fig. E/p distribution in pT bins. The distributions are fit with Gaussian + Exponent. Mean and SIgma were extracted from the fitting. The red line indicated 2 sigma (mean+- 2 sigma) position and the blue line indicates 3 sigma position.

- Fig. E/p mean position as a function of pT.

- Fig. E/p sigma position as a function of pT.

- Fig. Raw electron yields with 3 different n Sigma cuts (+-1, +-2 and +-3).

- The E/p mean deviates from 1.
- Issues with the fit (Gauss+bg) - Shingo is now working on that
- EMCal: calibration
- EMCal: residual non-linearities (low-pT)

- The E/p sigma goes from max 8.5% at low-pT to 5.5% at 5.5 GeV (3% at 6.5 GeV)
- this behavior is not unexpected - actually consistent with the beam test results and tracking pT-resolution (however small in this kinematic regime)

- for 1sigma: 10% effect for all pT's
- for 2 and 3 sigma: from 1-few% effect at low-pT to 10% max at high-pT (max deviation ~20% at 5.5 GeV but suffering from the stat uncertainty) - average: ~4%
- important note: the actual signal for the analysis is well within 3sigma and the systematic uncertainty for the related to these effects is driven by the 3sigma selection

- ratio is 1 with in error
- ~5 % difference at low pT due to 3 sigma position on the hadron tail.

Estimated efficiency of nSigma dE/dx cut (-1.5 < nSigma < 3.0 cut) by fitting the distribution with double Gaussian.

- the fits look reasonable at low-pT, however the high-pT systematics will suffer from the statistics
- the nSIgma efficiency (-1.5 < nSigma < 3.0) extracted from the fits is constant at 93% (for all pT's)
- expected from a Gaussian distribution

- the uncertainties extracted from variations of charge selection, rapidity ranges and E/p range show few to max 9.5% (relative) deviation
- note here is that the ranges for E/p taken within 0.8 - 1.0 and 1.3 E/p are overestimating the uncertainty due to limited statistics at high pT.

Checked eID efficiency from EMCal (matching + E/p) by using V0 and MC.

- V0 information comes from
- AliHFEcontainer
**hfe = (AliHFEcontainer**)base->FindObject("containerV0"); - AliCFContainer *sumcontainer = hfe->GetCFContainer("taggedTrackContainerReco");

* V0 cut

- v0trackCuts->CreateStandardCuts();
- v0trackCuts->SetMinNClustersTPC(120);
- v0trackCuts->SetMinNClustersTPCPID(80);
- v0trackCuts->SetMinRatioTPCclusters(0.6);
- v0trackCuts->SetTPCmodes(AliHFEextraCuts::kFound, AliHFEextraCuts::kFoundOverFindable);
- v0trackCuts->SetMinNClustersITS(1);
- v0trackCuts->SetCutITSpixel(AliHFEextraCuts::kAny);
- v0trackCuts->SetCheckITSLayerStatus(kFALSE);
- v0trackCuts->UnsetVertexRequirement();

* Used MC sample ; 10f6a (MB)

-0.6<y<0.6 (half E/p > mean)

-0.6<y<-0.2 (half E/p > mean)

-0.2<y<0.2 (half E/p > mean)

0.2<y<0.6 (half E/p > mean)

1. V0 (eta window / full eta)

2. MC (eta window / full eta)

-0.6<y<0.6 (0.8< E/p < 1.3)

-0.6<y<-0.2 (0.8< E/p < 1.3)

-0.2<y<0.2 (0.8< E/p < 1.3)

0.2<y<0.6 (0.8 < E/p < 1.3)

1. V0 (eta window / full eta)

2. MC (eta window / full eta)

MC/V0 in different windows

-0.6<y<0.6

-0.6<y<-0.2

-0.2<y<0.2

0.2<y<0.6

- the studies are done in pT of the electrons, two E/p cuts (E/p > mean --- pure electron sample, 0.8 < E/p < 1.3) and three selections of rapidity: -0.6<y<0.2; -0.2<y<0.2; 0.2<y<0.6
- general note is that statistics limits the clarity of the conclusions, however:
- V0/MC in rapidity windows indicates that
- a small relative rapidity dependence of V0 efficiency, the ratio is increasing from negative eta to positive eta especially low pT. The trend is not only E/p > mean but also 0.8 < E/p < 1.3.
- the observed deviation at high pT is mostly driven by the positive rapidity interval - relative 20% effect and above => the V0 efficiency is lower at y>0

- similar observation can be drawn from the purified/all electron studies but the effect on the order of 15%
- eta window / full eta ratio also indicates the eta dependence in V0 efficiency.

1. selected half E/p distribution - E/p greater than mean of the distribution

80<phi<100 (half E/p > mean)

100<phi<120 (half E/p > mean)

2. phi dependence ; 0.8 <E/p < 1.3

80<phi<100 (0.8< E/p < 1.3)

100<y<120 (0.8< E/p < 1.3)

efficiency from 0.8 <E/p < 1.3 is scaled by 0.5

80 < phi < 100

100 < phi < 120

- the studies as a function of the azimuthal angle agree within the stat uncertainties - at least drawing a systematic effect (for V0 vs MC efficiency) is not clear; however it is clear that the V0 efficiency (within the E/p systematics) shows a much stronger pT dependence as compared to MC - especially for the 100 < phi < 120 bin - however, it is impossible to conclude as within the kinematic region of the measurement (above 1.5 GeV) the curves agree and the stat precision above is limited

- Track matching cut ; R = sqrt(deta^{2}+dphi^{2}) < 0.05

- low pT ; V0 MC and V0 data is same RMS as Data
- high pT ; due to statistical limit, it's difficult to make conclusion. But MC is smaller than Data and V0 which is expected efficiency curve.

- SInce V0 efficiency is lower than MC, the cross section corrected by V0 efficiency is larger than the one corrected by MC. In addition that the HFE cross section is obtained by non-HEE contribution which is large contribution at low pT. This large background enhances the difference. Thus we see the large difference between the two cross section at low pT region.
- for example, at pT = 2 GeV/c, non-HFE cross section is ~ 0.9 x 10^-3. The MC corrected cross section is ~1x10^-3, and V0 corrected cross section is ~ 1.2 x 10^-3. After subtracting non-HFE cross section, it makes X3 difference

- HFE cross section corrected with MC and V0 is consistent within the uncertainty.

- V0 & MC indicates rapidity dependence of the efficiency (still working)
- the MC efficiency is under better control
- from the comparison to V0 we see a 5-15% relative discrepancy, and this should be taken into the systematic uncertainties, however further studies with a much larger data sample
- also, the 15% uncertainty seems to be an overestimation in this case as this is a max deviation and is strongly suffers from the statistics of the data sets

-- ShingoSakai - 27-Jan-2012

I | Attachment | History | Action | Size | Date | Who | Comment |
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c | Comp_eta_eta_eff.C | r1 | manage | 4.7 K | 2012-01-29 - 12:58 | Ssakai | |

root | MCeopEff1_phi.root | r1 | manage | 5.7 K | 2012-01-28 - 22:54 | Ssakai | |

png | Pic_HFEcomp.png | r2 r1 | manage | 18.3 K | 2012-02-05 - 15:04 | Ssakai | |

png | Pic_HFEcompHalf_ol.png | r1 | manage | 19.4 K | 2012-02-06 - 14:18 | Ssakai | |

png | Pic_HFEcomp_v1.png | r2 r1 | manage | 18.6 K | 2012-02-05 - 15:48 | Ssakai | |

png | Pic_HFEfixsig_comp2.png | r1 | manage | 20.6 K | 2012-02-06 - 23:42 | Ssakai | |

png | Pic_Inccomp.png | r6 r5 r4 r3 r2 | manage | 13.6 K | 2012-02-05 - 15:19 | Ssakai | |

png | Pic_Inccomp_v1.png | r1 | manage | 19.0 K | 2012-02-05 - 15:42 | Ssakai | |

png | Pic_Inclusive_eopcutdep.png | r1 | manage | 9.8 K | 2012-02-04 - 19:00 | Ssakai | |

png | Pic_MCEopEff.png | r1 | manage | 14.2 K | 2012-02-01 - 00:15 | Ssakai | |

png | Pic_MCEopEff_all.png | r2 r1 | manage | 12.0 K | 2012-02-02 - 10:06 | Ssakai | |

png | Pic_MCmatchEff.png | r1 | manage | 14.6 K | 2012-02-01 - 00:15 | Ssakai | |

png | Pic_MCmatchEff_all.png | r3 r2 r1 | manage | 12.3 K | 2012-02-02 - 10:06 | Ssakai | |

png | Pic_Raw_yield_eta.png | r3 r2 r1 | manage | 16.0 K | 2012-02-01 - 17:10 | Ssakai | |

png | Pic_Raw_yield_eta_2sig.png | r1 | manage | 14.4 K | 2012-02-01 - 16:46 | Ssakai | |

png | Pic_Raw_yield_eta_ratio.png | r1 | manage | 21.4 K | 2012-01-31 - 22:34 | Ssakai | |

png | Pic_Rmatch_highRMS.png | r2 r1 | manage | 7.8 K | 2012-02-04 - 23:39 | Ssakai | |

png | Pic_Rmatch_highRMSv1.png | r1 | manage | 10.5 K | 2012-02-04 - 23:57 | Ssakai | |

png | Pic_Rmatch_lowRMS.png | r1 | manage | 8.3 K | 2012-02-04 - 23:13 | Ssakai | |

png | Pic_Rmatch_lowRMSv1.png | r1 | manage | 10.2 K | 2012-02-04 - 23:58 | Ssakai | |

png | Pic_V0EopEff.png | r1 | manage | 14.4 K | 2012-01-31 - 14:54 | Ssakai | |

png | Pic_V0MCeffFullComp.png | r1 | manage | 17.3 K | 2012-02-01 - 16:25 | Ssakai | |

png | Pic_V0eopEff_all.png | r2 r1 | manage | 12.3 K | 2012-02-01 - 14:17 | Ssakai | |

png | Pic_V0matchEff.png | r1 | manage | 14.8 K | 2012-01-31 - 11:38 | Ssakai | |

png | Pic_V0matchEff_all.png | r2 r1 | manage | 12.1 K | 2012-02-01 - 14:17 | Ssakai | |

png | Pic_YieldRatio.png | r1 | manage | 13.1 K | 2012-01-27 - 16:09 | Ssakai | |

png | Pic_Yield_Ratio_eopcut.png | r2 r1 | manage | 9.9 K | 2012-02-02 - 09:58 | Ssakai | |

png | Pic_Yield_Ratio_eopcut_v1.png | r1 | manage | 9.9 K | 2012-02-02 - 09:54 | Ssakai | |

png | Pic_eff_competa_full.png | r2 r1 | manage | 17.6 K | 2012-01-29 - 16:17 | Ssakai | |

png | Pic_eff_competa_full_v1.png | r1 | manage | 16.3 K | 2012-02-01 - 09:46 | Ssakai | |

png | Pic_eff_competa_full_v2.png | r1 | manage | 15.3 K | 2012-02-01 - 19:00 | Ssakai | |

png | Pic_eff_competa_half.png | r1 | manage | 18.0 K | 2012-01-29 - 15:36 | Ssakai | |

png | Pic_eff_competa_half_v1.png | r1 | manage | 16.9 K | 2012-02-01 - 09:31 | Ssakai | |

png | Pic_eff_competa_half_v2.png | r1 | manage | 15.4 K | 2012-02-01 - 18:58 | Ssakai | |

png | Pic_eff_eta0.png | r3 r2 r1 | manage | 21.8 K | 2012-01-27 - 20:21 | Ssakai | |

png | Pic_eff_eta0_comp.png | r2 r1 | manage | 20.3 K | 2012-01-28 - 00:58 | Ssakai | |

png | Pic_eff_eta0_full.png | r1 | manage | 12.4 K | 2012-01-27 - 21:52 | Ssakai | |

png | Pic_eff_eta1.png | r3 r2 r1 | manage | 21.6 K | 2012-01-27 - 20:22 | Ssakai | |

png | Pic_eff_eta1_comp.png | r2 r1 | manage | 20.6 K | 2012-01-28 - 00:58 | Ssakai | |

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png | Pic_eff_eta2.png | r3 r2 r1 | manage | 21.5 K | 2012-01-27 - 20:22 | Ssakai | |

png | Pic_eff_eta2_comp.png | r2 r1 | manage | 20.1 K | 2012-01-28 - 00:59 | Ssakai | |

png | Pic_eff_eta2_full.png | r1 | manage | 22.3 K | 2012-01-27 - 21:52 | Ssakai | |

png | Pic_eff_eta3.png | r3 r2 r1 | manage | 21.8 K | 2012-01-27 - 20:22 | Ssakai | |

png | Pic_eff_eta3_comp.png | r2 r1 | manage | 19.6 K | 2012-01-28 - 00:59 | Ssakai | |

png | Pic_eff_eta3_full.png | r1 | manage | 22.1 K | 2012-01-27 - 21:52 | Ssakai | |

png | Pic_eff_phi0.png | r1 | manage | 21.5 K | 2012-01-28 - 22:32 | Ssakai | |

png | Pic_eff_phi0_comp.png | r1 | manage | 22.0 K | 2012-01-29 - 16:05 | Ssakai | |

png | Pic_eff_phi0_comp_v1.png | r1 | manage | 22.0 K | 2012-01-29 - 16:24 | Ssakai | |

png | Pic_eff_phi0_full.png | r1 | manage | 21.9 K | 2012-01-28 - 22:43 | Ssakai | |

png | Pic_eff_phi1.png | r1 | manage | 21.5 K | 2012-01-28 - 22:32 | Ssakai | |

png | Pic_eff_phi1_comp.png | r1 | manage | 22.6 K | 2012-01-29 - 16:05 | Ssakai | |

png | Pic_eff_phi1_comp_v1.png | r1 | manage | 22.6 K | 2012-01-29 - 16:28 | Ssakai | |

png | Pic_eff_phi1_full.png | r1 | manage | 21.8 K | 2012-01-28 - 22:43 | Ssakai | |

png | Pic_eff_ratio_eta_MC.png | r1 | manage | 13.9 K | 2012-01-29 - 13:13 | Ssakai | |

png | Pic_eff_ratio_eta_MC_full.png | r1 | manage | 14.0 K | 2012-01-29 - 13:28 | Ssakai | |

png | Pic_eff_ratio_eta_MC_full_v2.png | r2 r1 | manage | 12.9 K | 2012-02-01 - 09:59 | Ssakai | |

png | Pic_eff_ratio_eta_MC_full_v3.png | r1 | manage | 13.5 K | 2012-02-01 - 18:34 | Ssakai | |

png | Pic_eff_ratio_eta_MC_v1.png | r1 | manage | 12.7 K | 2012-02-01 - 09:34 | Ssakai | |

png | Pic_eff_ratio_eta_MC_v3.png | r1 | manage | 13.2 K | 2012-02-01 - 18:41 | Ssakai | |

png | Pic_eff_ratio_eta_V0.png | r1 | manage | 14.7 K | 2012-01-29 - 13:13 | Ssakai | |

png | Pic_eff_ratio_eta_V0_full.png | r1 | manage | 14.4 K | 2012-01-29 - 13:27 | Ssakai | |

png | Pic_eff_ratio_eta_V0_full_v1.png | r1 | manage | 13.3 K | 2012-02-01 - 09:52 | Ssakai | |

png | Pic_eff_ratio_eta_V0_full_v3.png | r1 | manage | 13.7 K | 2012-02-01 - 18:34 | Ssakai | |

png | Pic_eff_ratio_eta_V0_v1.png | r1 | manage | 13.3 K | 2012-02-01 - 09:34 | Ssakai | |

png | Pic_eff_ratio_eta_V0_v3.png | r1 | manage | 13.8 K | 2012-02-01 - 18:42 | Ssakai | |

png | Pic_eop_fit_expgau.png | r1 | manage | 29.0 K | 2012-01-27 - 14:16 | Ssakai | |

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png | Pic_eop_fix_expgau_v1.png | r1 | manage | 26.9 K | 2012-02-01 - 17:47 | Ssakai | |

png | Pic_eop_fix_expgau_v2.png | r1 | manage | 26.9 K | 2012-02-01 - 17:48 | Ssakai | |

png | Pic_half_eop_ratio.png | r1 | manage | 12.6 K | 2012-02-01 - 19:12 | Ssakai | |

png | Pic_mean_data.png | r1 | manage | 6.9 K | 2012-01-27 - 12:49 | Ssakai | |

png | Pic_mean_data_v1.png | r1 | manage | 6.2 K | 2012-02-01 - 07:34 | Ssakai | |

png | Pic_nSigYield.png | r2 r1 | manage | 12.8 K | 2012-01-28 - 16:11 | Ssakai | |

png | Pic_nSigYield_ratio.png | r2 r1 | manage | 8.0 K | 2012-01-28 - 22:13 | Ssakai | |

png | Pic_nSigYield_ratio_v1.png | r1 | manage | 11.6 K | 2012-02-01 - 07:30 | Ssakai | |

png | Pic_nSigYield_v1.png | r1 | manage | 12.2 K | 2012-02-01 - 07:33 | Ssakai | |

png | Pic_nSig_dis.png | r1 | manage | 29.3 K | 2012-01-28 - 18:40 | Ssakai | |

png | Pic_nSig_eff.png | r1 | manage | 9.0 K | 2012-01-28 - 17:24 | Ssakai | |

png | Pic_nSig_eff_sys.png | r1 | manage | 13.6 K | 2012-01-28 - 18:36 | Ssakai | |

png | Pic_ratio_eopcutdep.png | r1 | manage | 12.5 K | 2012-02-04 - 22:13 | Ssakai | |

png | Pic_sig_data.png | r1 | manage | 8.3 K | 2012-01-27 - 12:49 | Ssakai | |

png | Pic_sig_data_v1.png | r1 | manage | 7.7 K | 2012-02-01 - 07:33 | Ssakai | |

png | pic_sysnSig.png | r2 r1 | manage | 8.8 K | 2012-02-02 - 15:03 | Ssakai |

This topic: Main > TWikiUsers > ShingoSakai > Analysis > 01272012

Topic revision: r48 - 2012-02-22 - Ssakai

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