Blue = PU2
Green = PU20
Red = PU40
Sigma vs Eta with PU 2 20 40 60
This plot was generated by taking the two superclusters which are closest to the two generated electrons from the dielectron gun. A ratio is taken of the energy of the supercluster over the energy of the matched electron. The width of this ratio represents the resolution of the reconstruction in ECAL. The high side tail is shown to increase as a function of |h|. the small collection of events at 0 represent very low energy superclusters that were matched to electrons yielding a ratio close to 0 GeV. This plot does not show the events in which the electron goes into a gap between segments in the detector. This also requires that the dR between electron and supercluster be equal to or less than .15.
This shows a subset of the same collection depicted above, the electrons exclusively within the barrel. The effect of pile up on width exclusively within the barrel seems to be reduced from the detector as a whole. This suggests that pile up has a larger effect on the endcap than on the barrel.
This shows the subset of events in which the electron is matched to a supercluster within the endcap. The effect of pile up on resolution is greatly increased here when compared to the barrel. It is hypothysised that in-spiral is a non-trival reason why pile up would have a larger effect in the endcap than on the barrel.
This shows the electron matches which have gone into the |h| range from (1.5 - 2.0). This is shown to view the effects of pile up within specific ranges of |h| and observe weither or not higher ranges of |h| have a poorer resolution from pile up.
Here is the farthest range of |h| that can be detected in the ECAL (2.5 - 3.0). Here the effect of pile up appears to have the largest effect on resolution. This opinion does not consider any intrinsict resolution differences within different |h| ranges in ECAL.