1,911 research outputs found
Interaction of mesons with a three-nucleon system
A study of the -3N interaction in the energy region near the -^3H
elastic scattering threshold is presented. The calculational scheme is based on
the four-body scattering formalism. A manageable form of the integral equations
is achieved by using a separable ansatz for the driving two-body - and
NN-forces as well as for the subamplitudes appearing in the (1+3) and (2+2)
partitions of the -3N system. Results presented for the -^3H
scattering length point to the existence of a virtual (antibound) s-wave
-^3H state. As a consequence, a large enhancement of the cross section
for -production from three-body nuclei is predicted.Comment: 4 pages including 2 eps-figures, Contribution to MESON 2002, 7th Int.
Workshop on Production, Properties and Interaction of Mesons, Cracow, Poland,
May 24-28, 200
Analysis of the low-energy NN-dynamics within a three-body formalism
The interaction of an -meson with two nucleons is studied within a
three-body approach. The major features of the -system in the
low-energy region are accounted for by using a s-wave separable ansatz for the
two-body - and -amplitudes. The calculation is confined to the
and configurations which are assumed to be the
most promising candidates for virtual or resonant -states. The
eigenvalue three-body equation is continued analytically into the nonphysical
sheets by contour deformation. The position of the poles of the three-body
scattering matrix as a function of the -interaction strength is
investigated. The corresponding trajectory, starting on the physical sheet,
moves around the three-body threshold and continues away from the
physical area giving rise to virtual -states. The search for poles on
the nonphysical sheets adjacent directly to the upper rim of the real energy
axis gives a negative result. Thus no low-lying s-wave -resonances
were found. The possible influence of virtual poles on the low-energy -scattering is discussed.Comment: 16 pages revtex including 10 figure
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