Effects of Finite Top Lifetime at the tt̄ Threshold
نویسندگان
چکیده
In this talk electroweak corrections related to the finite top quark lifetime to the total top pair threshold ee cross section at NNLL order are discussed. We include the absorptive parts in electroweak matching conditions of the NRQCD operators related to the top decay and use the optical theorem. Gauge invariance is maintained. The corrections lead to ultraviolet phase space divergences and NLL mixing effects. The corrections can amount to several percent and are phenomenologically relevant.
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