Blue = PU2
Green = PU20
Red = PU40
Pile Up 2 = Blue
Pile Up 20 = Green
Pile up 40 = Red
Energy of the Superclusters located exclusivly within the barrel (0.0 < #eta < 1.48). The effect of pile up increases the number of low energy Superclusters that are formed. This is expressed in the peak at low energies. The flat distrabution across the majority of the energy band is a representation of the flat distrabution simulated by the dielectron gun simulation. A quick drop off at 500 GeV occurs because the simuation only was set create electrons up to 500 GeV.
Energy of the Super Clusters located exclusivly within the endcap (1.5 < #eta 3.0). Here the effect of pile up creating low energy Superclusters is more pronounced. One hypothesis for this having a larger effect within the endcap is the number of minbias particles that are below the in-spiral threshold. The flat disbrabution of the simulation is shown again and a sharp drop off at 500 GeV again occurs.
This shows the total collection of unmatched superclusters in the detector. This is the of the suberclusters that were not matched to an electron from the dielectron gun. Thus ,apart from misreconstruction, this is the collection of superclusters that were created exclusively due to pile up. The two seperate peaks show that the minbias particles statistically tend to form superclusters at two different energies. As pile up increase it can be seen that both number of superclusters formed and mean energy of the supercluster go up.
This is the collection of unmatched superclusters that are within the barrel. It appears to be a zoomed in image of the smaller peak on the collection of all unmatched superclusters. The relation between increasing pile up and increasing number and energy of the supercluster collection is visble here as well. The drop off at 0 GeV is a shape which indicates that there is an energy cut on an element of the reconstruction. There is also a drop in the high side tail which is most noticeable in the 20 and 40 pile up case.
This is the collection of unmatched superclusters that are within the endcap. This appears to be the higher of the peaks seen on the plot of all unmatched superclusers. Again the relation between increasing pile up and increasing number and energy of the supercluster collection is visble. The cut near 0 GeV here occurs at a higher energy. The high side tail is smooth and continuous for all three pile up simulations. There are many more unmatched superclusers within the endcap as compared to the barrel. This is believed to be mostly due to in-spiral.