Preliminary Measurements of the

Preliminary Measurements of the Time Dependence of B 0 d ? B 0 d Mixing with Kaon and Charge Dipole Tags The SLD Collaboration ? Abstract We report two preliminary measurements of the time dependence of B 0 d ? B 0 d mixing using novel techniques with a sample of 150,000 hadronic Z 0 decays collected by the SLD experiment at the SLC. B decay vertices are reconstructed inclusively with a topological technique and the B hadron avor at production is determined by exploiting the large left-right forward-backward asymmetry of Z 0 ! b b decays in combination with a jet charge technique. Two methods are used to tag the B avor at decay. The rst uses the charge of kaons attached to the B decay vertex and identiied with the Cherenkov Ring Imaging Detector. The second measurement is based on the construction of a charge dipole of the topological vertices to separate the B 0 d =B 0 d decays by exploiting the B ! D cascade charge structure. The measurement of the oscillation frequency yields m d = 0:58 0:07(stat)0:08(syst) ps ?1 and 0:56 0:08(stat)0:04(syst) ps ?1 for the kaon and dipole tags respectively.