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arXiv · 1403.7302

D-Dbar Mixing in the Standard Model and Beyond from Nf=2 Twisted Mass QCD

N. Carrasco·M. Ciuchini·P. Dimopoulos·R. Frezzotti·V. Gimenez·V. Lubicz·G. C. Rossi·F. Sanfilippo·L. Silvestrini·S. Simula·C. Tarantino
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Abstract

We present the first unquenched lattice QCD results for the bag parameters controlling the short distance contribution to D meson oscillations in the Standard Model and beyond. We have used the gauge configurations produced by the European Twisted Mass Collaboration with Nf = 2 dynamical quarks, at four lattice spacings and light meson masses in the range 280-500 MeV. Renormalization is carried out non-perturbatively with the RI-MOM method. The bag-parameter results have been used to constrain New Physics effects in D-Dbar mixing, to put a lower bound to the generic New Physics scale and to constrain off-diagonal squark mass terms for TeV-scale Supersymmetry.

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N. Carrasco, M. Ciuchini, P. Dimopoulos, R. Frezzotti, V. Gimenez, V. Lubicz, G. C. Rossi, F. Sanfilippo, L. Silvestrini, S. Simula, C. Tarantino. 2014-06-13. D-Dbar Mixing in the Standard Model and Beyond from Nf=2 Twisted Mass QCD. https://doi.org/10.1103/physrevd.90.014502

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