出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We present a new method for determining K !pp matrix elements from lattice simulations that is less costly than direct simulations of K ! pp at physical kinematics. It improves, however, upon the traditional “indirect” approach of constructing the K !pp matrix elements using NLO SU(3) cPT, which can lead to large higher-order chiral corrections. Using the explicit example of the DI = 3=2 (27;1) operator to illustrate the method, we obtain a value for Re(A2) that agrees with experiment and has a total uncertainty of < 20%. Although our simulations use domain-wall valence quarks on the MILC asqtad-improved gauge configurations, this method is more general and can be applied to calculations with any fermion formulation.
