ET Correction Factor Study using Single Particles

In all of my previous correction factor studies, the simulations were set up so that one particle was thrown into the endcap while several other mesons were thrown in the negative Z direction. These particles were included to help define a vertex. Figure 4 in my last analysis has two points which are less than one, suggesting that the detector registered an ET greater than the thrown Pt. I thought that the extra energy may be comming from particles radiated from the backwards moving mesons. To test this hypothesis, I created simulations without the backwards thrown mesons so that now each event had only one particle. I also increased the number of events per Pt bin from 5000 to 25000. Aside from these two changes, this analysis is identical to the last. I throw electrons, photons, and pions at 1, 2, 5, 10, 15, 20, 30, 40, and 50GeV and detect ET in a 3X3 patch as well as over the full end-cap and the correction factor is still calculated by taking the thrown Pt divided by the mean of a gaussian fit to the detected ET spectrum. NOTE: Due to a typo, the thrown Pt of the 2GeV electron is bad. Disregard the 2GeV bin for electrons in this analysis.

The plots of the detected ET spectra fitted with gaussians using the calorimeter only geometry can be found below. The spectra detected by a 3X3 patch and the spectra detected using the full end-cap are shown:

• Electrons:  3X3 Patch     Full End-Cap
• Photons:    3X3 Patch     Full End-Cap
• Pions:        3X3 Patch     Full End-Cap

Fig 1: This plot shows the correction factors for the calorimeter only geometry using the ET detected in the 3X3 patch.

Fig 2: This plot shows the correction factors for the calorimeter only geometry using the ET detected in the full endcap.

The plots of the detected ET spectra fitted with gaussians using the full geometry can be found below. The spectra detected by a 3X3 patch and the spectra detected using the full end-cap are shown:

• Electrons:  3X3 Patch     Full End-Cap
• Photons:    3X3 Patch     Full End-Cap
• Pions:        3X3 Patch     Full End-Cap

Fig 3: This plot shows the correction factors for the full geometry using the ET detected in the 3X3 patch.

Fig 4: This plot shows the correction factors for the full geometry using the ET detected in the full endcap.

 In addition to calculating the correction factor by taking the mean of the gaussian fit of the detected ET spectrum, I have also calculated the correction factor on an event by event basis by dividing the thrown Pt by the detected ET. I then plotted the correction factor for each event vs. eta and phi. The below plots used the ET detected by the full end-cap with the condition that the high tower not be in etabins 1 or 12. Similar plots using the 3X3 patch and without the etabin condition can be found in the pdf files at the end of the page.

Calorimeter Only Geometry:

• Electrons:  Vs Eta     Vs Phi
• Photons:    Vs Eta     Vs Phi
• Pions:        Vs Eta     Vs Phi

Full Geometry:

• Electrons:  Vs Eta     Vs Phi
• Photons:    Vs Eta     Vs Phi
• Pions:        Vs Eta     Vs Phi 

 In addition to the above plots, I have generated plots showing the properties of the thrown particles as well as plots of the event by event correction factors vs eta and phi using different selection criteria. These plots can be found in the following PDF files.

Calorimeter Only Geometry: Electrons  Photons  Pions

Full Geometry:  Electrons  Photons  Pions