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arXiv · nucl-ex/0305019

Precision neutron interferometric measurement of the nd coherent neutron scattering length and consequences for models of three-nucleon forces

Abstract

We have performed the first high precision measurement of the coherent neutron scattering length of deuterium in a pure sample using neutron interferometry. We find b_nd = (6.665 +/- 0.004) fm in agreement with the world average of previous measurements using different techniques, b_nd = (6.6730 +/- 0.0045) fm. We compare the new world average for the nd coherent scattering length b_nd = (6.669 +/- 0.003) fm to calculations of the doublet and quartet scattering lengths from several modern nucleon-nucleon potential models with three-nucleon force (3NF) additions and show that almost all theories are in serious disagreement with experiment. This comparison is a more stringent test of the models than past comparisons with the less precisely-determined nuclear doublet scattering length of a_nd = (0.65 +/- 0.04) fm.

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T. C. Black, P. R. Huffman, D. L. Jacobson, W. M. Snow, K. Schoen, M. Arif, H. Kaiser, S. K. Lamoreaux, S. A. Werner. 2003-05-21. Precision neutron interferometric measurement of the nd coherent neutron scattering length and consequences for models of three-nucleon forces. https://doi.org/10.1103/physrevlett.90.192502

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