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SIGNATURES OF CP-VIOLATION IN THE PRESENCE OF MULTIPLE B-PAIR PRODUCTION AT HADRON COLLIDER

F. Halzen·M. C. Gonzalez-Garcia·T. Stelzer·R. A. Vazquez
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Abstract

We calculate the production of 2 b-quark pairs in hadron collisions. Sources of multiple pairs are multiple interactions and higher order perturbative QCD mechanisms. We subsequently investigate the competing effects of multiple b-pair production on measurements of CP-violation: i) the increase in event rate with multiple b-pair cross sections which may reach values of order 1 barn in the presence of multiple interactions and ii) the dilution of $b$ versus $\bar b$ tagging efficiency because of the presence of events with 4 $B$-mesons. The impact of multiple $B$-meson production is small unless the cross section for producing a single pair exceeds 1~mb. We show that even for larger values of the cross section the competing effects i) and ii) roughly compensate so that there is no loss in the precision with which CP-violating CKM angles can be determined.

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F. Halzen, M. C. Gonzalez-Garcia, T. Stelzer, R. A. Vazquez. 1995-03-22. SIGNATURES OF CP-VIOLATION IN THE PRESENCE OF MULTIPLE B-PAIR PRODUCTION AT HADRON COLLIDER. https://doi.org/10.1103/physrevd.51.4861

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