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arXiv · 1611.10175

Power Counting in Peripheral Partial Waves: The Singlet Channels

M. Pavón Valderrama·M. Sánchez Sánchez·C. -J. Yang·Bingwei Long·Jaume Carbonell·U. van Kolck
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Abstract

We analyze the power counting of the peripheral singlet partial waves in nucleon-nucleon scattering. In agreement with conventional wisdom, we find that pion exchanges are perturbative in the peripheral singlets. We quantify from the effective field theory perspective the well-known suppression induced by the centrifugal barrier in the pion-exchange interactions. By exploring perturbation theory up to fourth order, we find that the one-pion-exchange potential in these channels is demoted from leading to subleading order by a given power of the expansion parameter that grows with the orbital angular momentum. We discuss the implications of these demotions for few-body calculations: though higher partial waves have been known for a long time to be irrelevant in these calculations (and are hence ignored), here we explain how to systematize the procedure in a way that is compatible with the effective field theory expansion.

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M. Pavón Valderrama, M. Sánchez Sánchez, C. -J. Yang, Bingwei Long, Jaume Carbonell, U. van Kolck. 2016-11-30. Power Counting in Peripheral Partial Waves: The Singlet Channels. https://doi.org/10.1103/physrevc.95.054001

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