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arXiv · 1103.1494

Twisted mass chiral perturbation theory for 2+1+1 quark flavours

Gernot Münster·Tobias Sudmann
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Abstract

We present results for the masses of pseudoscalar mesons in twisted mass lattice QCD with a degenerate doublet of u and d quarks and a non-degenerate doublet of s and c quarks in the framework of next-to-leading order chiral perturbation theory, including lattice effects up to O(a^2). The masses depend on the two twist angles for the light and heavy sectors. For maximal twist in both sectors, O(a)-improvement is explicitly exhibited. The mixing of flavour-neutral mesons is also discussed, and results in the literature for the case of degenerate s and c quarks are corrected.

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Gernot Münster, Tobias Sudmann. 2011-03-14. Twisted mass chiral perturbation theory for 2+1+1 quark flavours. https://doi.org/10.1007/jhep04(2011)116

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