TY - JOUR
T1 - Kaon mixing matrix elements from beyond-the-standard-model operators in staggered chiral perturbation theory
AU - Bailey, Jon A.
AU - Kim, Hyung Jin
AU - Lee, Weonjong
AU - Sharpe, Stephen R.
PY - 2012/4/24
Y1 - 2012/4/24
N2 - Models of new physics induce K-K̄ mixing operators having Dirac structures other than the "left-left" form of the standard model. We calculate the functional form of the corresponding B parameters at next-to-leading order in both SU(3) and SU(2) staggered chiral perturbation theory (SChPT). Numerical results for these matrix elements are being generated using improved staggered fermions; our results can be used to extrapolate these matrix elements to the physical light and strange quark masses. The SU(3) SChPT results turn out to be much simpler than that for the standard model B K operator, due to the absence of chiral suppression in the new operators. The SU(2) SChPT result is of similar simplicity to that for B K. In fact, in the latter case, the chiral logarithms for two of the new B parameters are identical to those for B K, while those for the other two new B parameters are of opposite sign. In addition to providing results for the 2+1 flavor theory in SU(3) SChPT and the 1+1+1 flavor theory in SU(2) SChPT, we present the corresponding continuum partially quenched results, as these are not available in the literature.
AB - Models of new physics induce K-K̄ mixing operators having Dirac structures other than the "left-left" form of the standard model. We calculate the functional form of the corresponding B parameters at next-to-leading order in both SU(3) and SU(2) staggered chiral perturbation theory (SChPT). Numerical results for these matrix elements are being generated using improved staggered fermions; our results can be used to extrapolate these matrix elements to the physical light and strange quark masses. The SU(3) SChPT results turn out to be much simpler than that for the standard model B K operator, due to the absence of chiral suppression in the new operators. The SU(2) SChPT result is of similar simplicity to that for B K. In fact, in the latter case, the chiral logarithms for two of the new B parameters are identical to those for B K, while those for the other two new B parameters are of opposite sign. In addition to providing results for the 2+1 flavor theory in SU(3) SChPT and the 1+1+1 flavor theory in SU(2) SChPT, we present the corresponding continuum partially quenched results, as these are not available in the literature.
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U2 - 10.1103/PhysRevD.85.074507
DO - 10.1103/PhysRevD.85.074507
M3 - Article
AN - SCOPUS:84860115705
VL - 85
JO - Physical Review D - Particles, Fields, Gravitation and Cosmology
JF - Physical Review D - Particles, Fields, Gravitation and Cosmology
SN - 1550-7998
IS - 7
M1 - 074507
ER -