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arXiv · 0706.0955

Integrating out strange quarks in ChPT

Jurg Gasser·Christoph Haefeli·Mikhail A. Ivanov·Martin Schmid
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Abstract

We study three flavour chiral perturbation theory in a limit where the strange quark mass is much larger than the external momenta and the up and down quark masses, and where the external fields are those of two-flavour chiral perturbation theory. In this case, the theory reduces to the one of SU(2)_L x SU(2)_R. Through this reduction, one can work out the strange quark mass dependence of the LECs in the two-flavour case. We present the pertinent relations at two-loop order for F,B and l_i.

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Jurg Gasser, Christoph Haefeli, Mikhail A. Ivanov, Martin Schmid. 2007-06-26. Integrating out strange quarks in ChPT. https://doi.org/10.1016/j.physletb.2007.06.058

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