function of the Z ′ B − L boson mass for selected values of the coupling for both electron and muon final states at the LHC and, and for the electron channel only at the Tevatron. The muon channel at Tevatron requires more than 10 fb − 1 to start probing the Z ′ B − L boson at 3 σ , and, hence, we do not present it. We now fix some values for the coupling ( g ′ 1 = 0 . 158 , 0 . 1 , 0 . 08 for the LHC analysis, g ′ 1 = 0 . 1 , 0 . 08 for the Tevatron) and we see what luminosity is required for discovery at each machine. For g ′ 1 = 0 . 1 the LHC requires 0 . 35 − 0 . 70 fb − 1 to be sensitive at 5 σ , with electrons and muons, respectively, while Tevatron requires 10 fb − 1 with electrons. For the same value of the coupling, the Tevatron can discover the Z ′ B − L boson up to M$_{Z}$ ′ = 840 GeV, with electrons in the final state, with 12 fb − 1 of data. The LHC can extend the Tevatron reach up to M$_{Z}$ ′ = 1 . 0(0 . 9) TeV for g ′ 1 = 0 . 1. Regarding g ′ 1 = 0 . 08, a discovery can be made chiefly with electrons, requiring 0 . 4(12) fb − $^{1}$, for masses up to 900(780) GeV at the LHC(Tevatron). For muons, the LHC requires 0 . 85 fb − 1 for masses up to 800 GeV. Both machines will be sensitive at 3 σ with much less integrated luminosities, requiring roughly 0 . 12 − 0 . 15(0 . 25 − 0 . 35) fb − 1 to probe the Z ′ B − L at the LHC for electrons(muons) in the final state, for g ′ 1 = 0 . 1 − 0 . 08. At the Tevatron, 5 . 5 fb − 1 are required for probing at 3 σ both values of the coupling, for electrons only. Finally, bigger values of the coupling, such as g ′ 1 = 0 . 158, can be probed just at the LHC, that is sensitive at 3 σ for masses up 1 . 45(1 . 35) TeV using electrons(muons) and at 5 σ for masses up to 1 . 2(1 . 15) GeV, requiring 0 . 2 − 0 . 6(0 . 3 − 0 . 9) fb − 1 at least, at 3 σ − 5 σ for electrons(muons). The 5 σ discovery potential for the LHC at √$_{s}$ = 7 TeV and for the Tevatron are sum- marised in table III, for selected values of couplings and integrated luminosities. Figure 5 shows the discovery potential for the Z ′ B − L boson at the LHC for 10 TeV CM energy, while figure 6 shows the integrated luminosity required for 3 σ evidence as well as for 5 σ discovery as a function of the Z ′ B − L boson mass, for selected values of the coupling constant, for both electron and muon channels. If we compare figure 5 to figure 3, we see that increasing the CM energy at the LHC allows to extend the kinematical reach of the machine towards bigger values of the mass for the Z ′ B − L boson. For 1 fb − $^{1}$, the maximum observable masses for √$_{s}$ = 7 TeV are 1 . 25(1 . 65) B. LHC at √ s = 10 TeV 14