Combined limit on $B^0_s$ oscillation frequency

Several techniques were used in ALEPH to search for B0_s oscillations: Dileptons, lepton-jet charge, kaon-lepton correlation, D_s-lepton and D_s-hadron events with multiple initial state tags. In order to achieve the highest sensitivity all these analyses can be combined. This combination is performed using the amplitude-fit technique. In each analysis the amplitude of the B0_s B0_s/bar oscillation is fitted as function of the oscillation frequency. This amplitude parameter should be 0, if no oscillation is observed, or one if an oscillation signal is present. Oscillations can be excluded for a certain frequency if A = 1 can be excluded. The individual amplitude spectra represent measurements of the same physical quantity and can be combined using straightforeward error propagation. The combined lower limit will be presented.