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The electrons exhibit a very tightly constrained response, whereas the majority of the pions have a very high chi^2 value. There is a peak at 1 in the pion data, but it is one tenth the height of the electron peak. This is most likely due to pion showers which deposit a significant portion of their energy in the EM calorimeter and are discontinuous.expected; the shape data for the pions showed small peaks at values near the electron peaks in all of the measurements