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arXiv · 1507.00269

On the minimality of the order p^6 chiral Lagrangian

Pedro Ruiz-Femenia·Mehran Zahiri-Abyaneh
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Abstract

A method to find relations between the operators in the mesonic Lagrangian of Chiral Perturbation Theory at order p^6 is presented. The procedure can be used to establish if the basis of operators in the Lagrangian is minimal. As an example, we apply the method to the two-flavour case in the absence of scalar and pseudo-scalar sources (s=p=0), and conclude that the minimal Lagrangian contains 27 independent operators.

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Pedro Ruiz-Femenia, Mehran Zahiri-Abyaneh. 2015-07-01. On the minimality of the order p^6 chiral Lagrangian. https://doi.org/10.1016/j.physletb.2015.10.042

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