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arXiv · 1206.1207

Causality bounds for neutron-proton scattering

Serdar Elhatisari·Dean Lee
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Abstract

We consider the constraints of causality and unitarity for the low-energy interactions of protons and neutrons. We derive a general theorem that non-vanishing partial-wave mixing cannot be reproduced with zero-range interactions without violating causality or unitarity. We define and calculate interaction length scales which we call the causal range and the Cauchy-Schwarz range for all spin channels up to J = 3. For some channels we find that these length scales are as large as 5 fm. We investigate the origin of these large lengths and discuss their significance for the choice of momentum cutoff scales in effective field theory and universality in many-body Fermi systems.

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Serdar Elhatisari, Dean Lee. 2012-06-06. Causality bounds for neutron-proton scattering. https://doi.org/10.1140/epja/i2012-12110-x

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