Z(dE/dx) distribution
In addition to the the TOF residual distribution, we use the Z(dE/dx) distribution to statistically separate the pion, kaon and proton components in data.
The parameterization of the dE/dx universal curve and the Z(dE/dx) distribution is obtained using a sample of generic tracks found in a cone of radius ΔR = 0.7 around reconstructed D* → D0 π decays.
An example plot of the Z(dE/dx) residual distribution (plotted assuming the pion mass hypothesis) is shown below:
The plots below show the projections of the parameterization used to describe the shape of the dE/dx universal curve:
