The Threshold tt̄ Cross Section at NNLL Order
نویسندگان
چکیده
The total cross section for top quark pair production close to threshold in e+e− annihilation is investigated. Details are given about the calculation at next-to-next-to-leading logarithmic order. The summation of logarithms leads to a convergent expansion for the normalization of the cross section, and small residual dependence on the subtraction parameter ν. A detailed analysis of the residual ν dependence is carried out. A conservative estimate for the remaining uncertainty in the normalization of the total cross section from QCD effects is δσtt̄/σtt̄ ∼ ±3%. This makes precise extractions of the strong coupling and top width feasible, and further studies of electroweak effects mandatory. Typeset using REVTEX
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تاریخ انتشار 2001