0.75 1 1.25 1.5 10 −2 10 −1 95% C.L. LHC: s=7 TeV Tevatron (L = 10fb$^{−1}$) Electrons Muons LHC (L = 100pb −1 ) Electrons Muons LHC (L = 1fb −1 ) M$_{Z’}$  (TeV) g’ 1 (a) 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 g’$_{1}$=0.158 g’$_{1}$=0.158 g’$_{1}$=0.1 LHC ( s=7 TeV), 95% C.L. Electrons Muons g’$_{1}$=0.1 g’$_{1}$=0.05 g’$_{1}$=0.05 1 1.25 1.5 M$_{Z’}$ (TeV) Int. Lum. (fb −1 ) 0.75 (b) 5 6 7 8 9 10 11 12 0.6 0.7 0.8 0.9 1 g’$_{1}$ = 0.1 g’$_{1}$ = 0.1 Tevatron, 95% C.L. Electrons Muons g’$_{1}$ = 0.05 g’$_{1}$ = 0.05 M$_{Z’}$ (TeV) Int. Lum. (fb −1 ) (c) FIG. 12: (12a) Contour levels for 95% C.L. plotted against g ′ 1 and M$_{Z}$ ′ at the LHC for selected integrated luminosities and integrated luminosity required for observation at 3 σ and 5 σ vs. M$_{Z}$ ′ for selected values of g ′ 1 (in which only the allowed combination of masses and couplings are shown), for (12b) the LHC at √$_{s}$ = 7 TeV and (12c) the Tevatron $_{(}$√$_{s}$ = 1 . 96 TeV), for both electrons and muons. The shaded areas and the allowed ( M$_{Z}$ ′ , g ′ $_{1}$) shown are in accordance with eq. (21) (LEP bounds, in black) and table II (Tevatron bounds, in red for electrons and in green for muons). 25