Figure 54

Relative resolution of $E/p$ vs. transverse momentum $\pt$ for electrons in experimental data (full dots) and from a fully reconstructed MC (open circles) in pp collisions at $\sqrt{s}$ = 7 TeV. The EMCal energy resolution deduced from the width of the ${\rm \pi^0}$ and $\eta$ invariant mass peaks (black dotted line), added in quadrature to the TPC $\pt$ resolution (green dash-dotted line), describes the measurement reasonably well (red solid line).