DOI: 10.1140/epja/i2001-10272-2
Subthreshold
-meson production in proton-nucleus reactions revisited
E.Ya. Paryev Institute for Nuclear Research, Russian Academy of Sciences, Moscow 117312, Russia Paryev@a120.INR.Troitsk.ru
(Received: 26 July 2001 / Revised version: 23 December 2002 / Published online: 8 April 2003)
Abstract
We study
the inclusive
K--meson production in proton-nucleus collisions
in the subthreshold energy regime in the framework of
a spectral function approach for incoherent primary
proton-nucleon and secondary pion-nucleon production processes.
Our approach takes properly into account the effect of the
nuclear mean-field potentials
on these processes, as well as the final-state interaction
(FSI) among the outgoing nucleons participating in the one-step
antikaon creation process. A detailed comparison
of the model calculations of the
K- differential cross-sections
for the reactions
,
, and
at subthreshold energies with the currently available experimental
data obtained recently at the ITEP proton synchrotron and at
SIS/GSI is given. We find that our calculation, which includes
both the nuclear density-dependent mean-field potentials
and the elementary
NN-FSI effects
on the
K- production from the direct mechanism, is able to
reproduce the energy dependences of the invariant differential
cross-sections for the "hard" antikaon creation in
p-
and
p-
collisions. This result contradicts previous estimates
which used only density-dependent mean fields in calculating the
K- yield from this mechanism. We further show that the
NN-FSI
effects play a minor role in describing the data on the spectrum of
the relatively soft
K--mesons from
p-
interactions at
incident energy of
. We find that the relative
strength of the proton- and pion-induced reaction channels in the
subthreshold energy regime is governed by the kinematics of
the experiment under consideration. We also explore the influence of
the antikaon mean-field potential on the
K- yield at low antikaon
momenta.
25.40.-h - Nucleon-induced reactions.
© Società Italiana di Fisica, Springer-Verlag 2003
