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arXiv · hep-ph/9510289

Increasing R_b and Decreasing R_c with New Heavy Quarks

Ernest Ma
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Abstract

If the b and c quarks mix with new heavy quarks of weak isospin I_3 = -1 and 0 respectively, then the Z -> b b(bar) (c c(bar)) rate is necessarily greater (smaller) than that of the standard model. This may be the reason for the R_b excess and R_c deficit observed at LEP. A possible consequence of this scenario is the prospective discovery of a new quark x with the dominant decay x -> c h, then h -> b b(bar), where h is a neutral Higgs boson.

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Ernest Ma. 1995-10-13. Increasing R_b and Decreasing R_c with New Heavy Quarks. https://doi.org/10.1103/physrevd.53.2276

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