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arXiv · hep-lat/9708005

Quenched Chiral Perturbation Theory to one loop

Gilberto Colangelo·Elisabetta Pallante
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Abstract

We calculate the divergences of the generating functional of quenched Chiral Perturbation Theory at one loop, and renormalize the theory by an appropriate definition of the counterterms. We show that the quenched chiral logarithms can be reabsorbed in the renormalization of the B_0 parameter which, at lowest order, is proportional to the vacuum expectation value of the scalar quark density. Finally, we calculate several quantities at one loop to analyze the modifications induced by quenching in the finite part of the one-loop corrections. We point out that some of the finite loop corrections may diverge in the chiral limit.

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Gilberto Colangelo, Elisabetta Pallante. 1998-02-25. Quenched Chiral Perturbation Theory to one loop. https://doi.org/10.1016/s0550-3213(98)00195-3

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