2019 Impact factor 2.176
Hadrons and Nuclei
Eur. Phys. J. A 9, 277-285

Production of a0-mesons in the reactions ${\pi N \to a_0 N}$and ${p p \to d a_0^+}$ at GeV energies

V.Yu. Grishina1 - L.A. Kondratyuk2 - E.L. Bratkovskaya3 - M. Büscher4 - W. Cassing3

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 Institut für Theoretische Physik, Universität Giessen, D-35392 Giessen, Germany
4 Institut für Kernphysik, Forschungszentrum Jülich, D-52425 Jülich, Germany

Received: 4 August 2000
Communicated by W. Weise

Abstract
We investigate the reactions ${\pi N \to a_0 N}$ and ${p p \to d a_0^+}$ near threshold and at medium energies. An effective Lagragian approach and the Regge pole model are applied to analyze different contributions to the cross-section of the reaction ${\pi N \to a_0 N}$. These results are used to calculate the differential and total cross-sections of the reaction ${p p \to d a_0^+}$ within the framework of the two-step model in which two nucleons produce an a0-meson via $\pi$-meson exchange and fuse to a deuteron. The necessity of new measurements on a0 production and branching fractions (of its decay to the $K\bar K$ and $\pi\eta$channels) is emphasized for clarifying the a0 structure. Detailed predictions for the reaction $pp \rightarrow d a_0^+$ are presented for the energy regime of the proton synchrotron COSY-Jülich.

PACS
25.10.+s Nuclear reactions involving few-nucleon systems - 13.75.-n Hadron induced reactions - 13.60.Le Meson production


Copyright Società Italiana di Fisica, Springer-Verlag 2000