Precision neutron interferometric measurement of the nd coherent neutron scattering length and consequences for models of three-nucleon forces.
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 doublet scattering length of (2)a(nd)=(0.65+/-0.04) fm.
Black
T C
TC
University of North Carolina at Wilmington, Wilmington, North Carolina 28403-3297, USA.
Huffman
P R
PR
Jacobson
D L
DL
Snow
W M
WM
Schoen
K
K
Arif
M
M
Kaiser
H
H
Lamoreaux
S K
SK
Werner
S A
SA