Performances of a trigger based on B-Jets tagging at CDF II

In this paper, we describe the development and the performance studies of a trigger devoted to the identification of b-jets final state events in pp interactions at the CDF II experiment of Tevatron collider at Fermilab. Exploiting new trigger primitives provided by two recent trigger upgrades, the Level2 XFT stereo tracking and the improved Level2 cluster- finder, in conjunction with the existing silicon vertex tracker (SVT), we design an online trigger algorithm aimed at selecting good purity 6-jets samples useful for many physics measurements, one of the most important being inclusive searches for the Standard Model Higgs boson. We describe the performances of the proposed algorithm, which must guarantee high efficiency on signal events while maintaining sustainable rate at the luminosity of 3ldr10³² cm^-2s^-1 reachable at the Tevatron.