Subthreshold and near threshold K+ meson production on light nuclei by protons
E.Ya. Paryev
Institute for Nuclear Research, Russian Academy of Sciences, 117312 Moscow, Russia
Received: 26 October 1998 / Revised version: 10 February 1999 Communicated by W. Weise
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 folding model,
which takes properly into account
the struck target nucleon removal energy and momentum
distribution (nucleon spectral function), novel elementary cross
sections for proton-nucleon reaction channel close to threshold
as well as nuclear mean-field potential effects on the one-step
and two-step kaon creation processes. A detailed comparison
of the model calculations of the K+ total and differential
cross sections for the reactions p+Be9 and 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. It is found that, contrary to previous
studies performed in the literature, the pion-nucleon production
channels do not necessarily dominate in pA collisions at subthreshold
energies and the relative strength of the proton and pion induced
reaction channels in light target nuclei in the subthreshold energy
regime is governed by the kinematics of experiment under consideration.
PACS
25.40.-hNucleon-induced reactions
Copyright Springer-Verlag
