Eur. Phys. J. A (2005) 25: 159-164
https://doi.org/10.1140/epja/i2005-10089-y

Original Article

The K^-α scattering length and the reaction dd↦αK⁺K^-

¹ Institute for Nuclear Research, 60th October Anniversary Prospect 7A, 117312, Moscow, Russia
² Institute of Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117259, Moscow, Russia
³ Helmholtz-Institut für Strahlen- und Kernphysik (Theorie), Universität Bonn, Nußallee 14-16, D-53115, Bonn, Germany
⁴ Institut für Kernphysik, Forschungszentrum Jülich, D-52425, Jülich, Germany

Received: 1 April 2005
Accepted: 10 June 2005
Published online: 23 June 2005

Abstract

We present predictions for the K ^-α scattering length obtained within the framework of the multiple-scattering approach. Evaluating the pole position of the K ^-α scattering amplitude within the zero-range approximation, we find a loosely bound K ^-α state with a binding energy of E _R = - 2,..., - 7 MeV and a width Γ_R = 11,..., 18 MeV. We propose to measure the K ^-α scattering length through the final-state interaction between the α and K^--meson produced in the reaction dd↦αK ⁺ K ^-. It is found that the K ^-α invariant-mass distribution from this reaction at energies near the threshold provides a new tool to determine the s-wave K ^-α scattering length.