ar X iv : h ep - p h / 03 02 27 5 v 2 3 A pr 2 00 3 Three Loop Top Quark Contributions to the ρ Parameter
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چکیده
We present results for the three-loop top quark contributions to the ρ parameter in the limit of large top quark mass. The simultaneous dependence on the mass of the Higgs boson M H and the mass of the top quark m t is obtained from expansions in the range of M H around m t and in the limit M H ≫ m t. In combination with the previous result for M H = 0 the dependence of the ρ parameter on the leading Yukawa contributions, i.e. on m t and M H , is well under control for all mass values of practical importance. The effects lead to a shift in the W mass in the order of 5 MeV and are relevant for precision measurements at TESLA.
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تاریخ انتشار 2003