Research Papers in Physics and Astronomy


Date of this Version

January 2004


Published by American Physical Society. Phys. Rev. D 69, 012002 (2004). Copyright © 2004 American Physical Society. Permission to use.


We have measured the number of like-sign (LS) and opposite-sign (OS) lepton pairs arising from double semileptonic decays of b and b-bar hadrons, pair produced at the Fermilab Tevatron collider. The data samples were collected with the Collider Detector at Fermilab during the 1992–1995 collider run by triggering on the existence of µµ or candidates in an event. The observed ratio of LS to OS dileptons leads to a measurement of the average time-integrated mixing probability of all produced b-flavored hadrons which decay weakly, Χ̅=0.152±0.007 (stat)±0.011 (syst), that is significantly larger than the world average Χ̅=0.118±0.005.

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