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arXiv · 1310.5461

$K$ and $D$ oscillations in the Standard Model and its extensions from $N_f=2+1+1$ Twisted Mass LQCD

Nuria Carrasco·Petros Dimopoulos·Roberto Frezzotti·Vicent Giménez·Vittorio Lubicz·Giancarlo Rossi·Francesco Sanfilippo·Silvano Simula·Cecilia Tarantino
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Abstract

We present the first $N_f=2+1+1$ results for the matrix elements of the operators describing neutral $K$ and $D$ mixing in the Standard Model and its extensions. The combination of maximally twisted sea quarks and Osterwalder-Seiler valence quarks ensures $\mathcal{O}(a)$-improvement and continuum like renormalization pattern. We have used the $N_f=2+1+1$ dynamical quark gauge configurations generated by ETMC. Simulations include three lattice spacings in the interval $[0.06:0.09]$ fm and pseudoscalar meson masses in the range $[230:500]$ MeV. Our results are extrapolated to the continuum limit and to the physical quark masses. The calculation of the renormalization constants has been performed non-perturbatively in the RI-MOM scheme.

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Nuria Carrasco, Petros Dimopoulos, Roberto Frezzotti, Vicent Giménez, Vittorio Lubicz, Giancarlo Rossi, Francesco Sanfilippo, Silvano Simula, Cecilia Tarantino. 2013-10-21. $K$ and $D$ oscillations in the Standard Model and its extensions from $N_f=2+1+1$ Twisted Mass LQCD. https://arxiv.org/abs/1310.5461

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