Measurement of the neutron-neutron scattering length <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>a</mi></mrow><mrow><mi mathvariant="normal">nn</mi></mrow></msub></mrow></math> with the reaction <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>π</mi></mrow><mrow><mi mathvariant="normal">−</mi></mrow></msup></mrow></math>d → nnγ in complete kinematics

O. Schori; B. Gabioud; C. Joseph; J. P. Perroud; D. Rüegger; M. T. Tran; P. Truöl; E. Winkelmann; W. Dahme

doi:10.1103/PhysRevC.35.2252

Milestone

Measurement of the neutron-neutron scattering length $a_{nn}$ with the reaction $π^{-}$ d → nnγ in complete kinematics

O. Schori, B. Gabioud, C. Joseph, J. P. Perroud, D. Rüegger, M. T. Tran, P. Truöl, E. Winkelmann, and W. Dahme

Phys. Rev. C 35, 2252 – Published 1 June 1987

An article within the collection: Physical Review C 50^th Anniversary Milestones

Abstract

The neutron-neutron scattering length $a_{nn}$ is determined from the low energy part of the neutron spectrum of the reaction $π^{-}$ d→nnγ with pions at rest. Since neutrons are detected in coincidence with the photon, the kinematics is completely determined. We obtain $a_{nn = - 18.7 \pm 0.6}$ fm, in agreement with a result of a previous experiment based on the analysis the photon spectrum.