The leading chiral electromagnetic correction to the nonleptonic ∆ I = 3 / 2 amplitude in kaon decays
نویسندگان
چکیده
In kaon decay, electromagnetic radiative corrections can generate shifts in the apparent ∆I = 3/2 amplitude of order αA0/A2 ∼ 22α. In order to know the true ∆I = 3/2 amplitude for comparison with lattice calculations and phenomenology, one needs to subtract off this electromagnetic effect. We provide a careful estimate of the leading electromagnetic shift in the chiral expansion of the amplitude, which shows that it is smaller than naive expectations, with a fractional shift of δA (em) 2 /A2 = −0.016± 0.01.
منابع مشابه
Chiral Perturbation Theory and Kaon Physics∗
A brief survey of applications of chiral perturbation theory to both semileptonic and nonleptonic kaon decays is presented. Special emphasis is given to recent theoretical advances related to semileptonic decays, in particular pion pion scattering and Ke4 decays. The systematic approach for including isospin violation and electromagnetic corrections in semileptonic kaon decays is discussed for ...
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تاریخ انتشار 1999