Subthreshold K+ meson production in proton-nucleus reactions and nucleon spectral function
S.V. Efremov1 - E.Ya. Paryev2
1 Bonner Nuclear Laboratory, Rice University, P.O. Box 1892,
Houston, TX 77005-1892, USA
2 Institute for Nuclear Research, Russian Academy of Sciences, Moscow 117312,
Russia
Received: 2 April 1997 / Revised version: 7 August 1997
Abstract
The inclusive K+ meson production in proton-nucleus
collisions in the near threshold and subthreshold energy regimes is analyzed
with respect to the one-step (,
) and
two-step (
) incoherent
production processes on the basis of an appropriate new folding model,
which takes properly into account the struck target nucleon removal energy
and momentum distribution (nucleon spectral function), extracted from
recent quasielastic electron scattering experiments and from many-body
calculations with realistic models of the NN interaction. Comparison
of the model calculations of the K+ total and double differential
cross sections for the reaction p+C12 with the existing experimental
data is given, illustrating both the relative role of the primary and
secondary production channels at considered incident energies and those
features of the cross sections which are sensitive to the high momentum and
high removal energy part of the nucleon spectral function that is governed
by nucleon-nucleon short-range and tensor correlations. It is found that
the in-medium modifications of the available for pion and kaon production
invariant energies squared due to the respective optical potentials are
needed to account for considered experimental data.
PACS
25.40.-k Nucleon induced reactions
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