Testing the f-nuclear potential in pion-induced f meson production on nuclei near threshold

The near-threshold pion-induced phi production off nuclei has been studied in the kinematical conditions of the HADES experiment using a collision model based on the nuclear spectral function. Starting from the elementary reaction pi (-) p -> phi n, absolute differential and integral cross sections for the production of phi mesons off a light carbon and a heavy tungsten target have been calculated and compared to the recently reported experimental cross sections. The absolute cross section values are shown to be sensitive to the effective nuclear scalar phi and neutron potentials while the transparency ratio is governed by the phi Nabsorption cross section. The experimental data are found to be consistent with an attractive phi-nucleus potential of approximate to -(50-100) MeV at normal nuclear matter density rho(0) and an effective phi Nabsorption cross section of approximate to 12-25 mb. The extracted phi-nucleus potential is deeper than previous theoretical and experimental findings as well as those obtained in the present work within the (t rho) approximation with accounting for Pauli correlations from the spin-averaged phi-pscattering length reported in a recent ALICE experiment. (c) 2023 Elsevier B.V. All rights reserved.