2020 Impact factor 3.043
Hadrons and Nuclei
Eur. Phys. J. A 7, 127-137

Subthreshold and near threshold K+ meson photoproduction
on nuclei

E.Ya. Paryev

Institute for Nuclear Research, Russian Academy of Sciences, Moscow 117312, Russia

Received: 12 April 1999 / Revised version: 11 September 1999 Communicated by W. Weise

Abstract
The inclusive K+ meson production in photon-induced reactions in the near threshold and subthreshold energy regimes is analyzed with respect to the one-step ( $\gamma N \to K^+Y$, $Y=\Lambda,\Sigma$) incoherent production processes on the basis of an appropriate new folding model, which takes properly into account the struck target nucleon removal energy and internal momentum distribution (nucleon spectral function), extracted from recent quasielastic electron scattering experiments and from many-body calculations with realistic models of the NN interaction. Simple parametrizations for the total and differential cross sections of the K+ production in photon-nucleon collisions are presented. Comparison of the model calculations of the K+ differential cross sections for the reaction $\gamma+C^{12}$ in the threshold region with the existing experimental data is given, that displays the contributions to the K+ production at considered incident energies coming from the use of the single-particle part as well as high momentum and high removal energy part of the nucleon spectral function. Detailed predictions for the K+ total and differential cross sections from $\gamma H^{2}$, $\gamma C^{12}$ and $\gamma Pb^{208}$ reactions at subthreshold and near threshold energies are provided. The influence of the uncertainties in the elementary K+ production cross sections on the K+ yield is explored.

PACS
25.20.Lj Photoproduction reactions - 21.80.+a Hypernuclei


Copyright Società Italiana di Fisica, Springer-Verlag 2000