$n_{\sigma}^{\rm{TPC}}$ distributions as a function of momentum in semi-central (20-40%) Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV. Upper left panel: no ITS or TOF electron identification is applied. Upper right panel: the TOF-PID (see text) is applied. Lower panel: the TOF and ITS-PID (see text) are both applied. | |