ET Correction Factor

I am doing a systematic study of the correction factor needed to make simulated detected ET match simulated thrown particle pt in the endcap. To this end, I have thrown single particle electron, photon and pion events using the final year 2006 geometry over the full eta-phi range of the endcap. For each particle species, I generated 5000 events at each of 9 different single thrown pt's: 1, 2, 5, 10, 15, 20, 30, 40, and 50GeV. I then calculate the correction factor at each pt by dividing the thrown pt by the mean of the ET distribution detected in a 3X3 patch centered on the tower with the most energy.

Fig 1: These plots show the detected ET distribution for each thrown pt. The plots contain less than 5000 events each because I discarded those events that had the highest energy tower in eta bins 1 or 12 to avoid edge effects. The top group of nine is the electrons, the middle group is the photons and the bottom group is the neutral pions.

Fig 2: These plots show a profile of the correction factor plotted vs eta fitted with a linear function. For these plots, the correction factor was calculated on an event by event basis by dividing the thrown pt by the detected ET. This is then plotted vs the particle track eta found from the geant record. For these plots, all eta bins are used to get an idea of what effect the edges have. The first group is electrons, the second is photons and the third is neutral pions.

Fig 3: This figure is the same as Fig 2 only now the correction factors are plotted vs phi and only events with the high tower in bins 2-11 are plotted. The same ordering as above applies.

Fig 4: This plot shows the correction factors calculated by dividing the thrown pt by the mean detected ET for each particle species.

PDF files displaying the quantities shown above as well as plots showing number of reconstructed and generated primary vertices, eta and phi distributions etc. can be found here: electrons, photons, pions.