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arXiv · hep-ph/0203087

Electromagnetic penguin operators and direct CP violation in K --> pi l^+ l^-

Giancarlo D'Ambrosio·Dao-Neng Gao
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Abstract

Supersymmetric extensions of the Standard Model predict a large enhancement of the Wilson coefficients of the dimension-five electromagnetic penguin operators affecting the direct CP violation in K_L --> pi^0 e^+ e^- and the charge asymmetry in K^\pm --> pi^\pm l^+ l^-. Here we compute the relevant matrix elements in the chiral quark model and compare these with the ones given by lattice calculations

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Giancarlo D'Ambrosio, Dao-Neng Gao. 2002-07-29. Electromagnetic penguin operators and direct CP violation in K --> pi l^+ l^-. https://doi.org/10.1088/1126-6708%2F2002%2F07%2F068

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