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arXiv · 1406.1359

Constraints on a possible dineutron state from pionless EFT

H. W. Hammer·Sebastian König
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Abstract

We investigate the sensitivity of the three-nucleon system to changes in the neutron-neutron scattering length to next-to-leading order in the pionless effective field theory, focusing on the the triton-3He binding energy difference and neutron-deuteron elastic scattering. Due to the appearance of an electromagnetic three-body counterterm at this order, the triton-3He binding energy difference remains consistent with the experimental value even for large positive neutron-neutron scattering lengths while the elastic neutron-deuteron scattering phase shifts are insensitive. We conclude that a bound dineutron cannot be excluded to next-to-leading order in pionless EFT.

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H. W. Hammer, Sebastian König. 2014-06-05. Constraints on a possible dineutron state from pionless EFT. https://doi.org/10.1016/j.physletb.2014.07.015

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