K+ PRODUCTION FROM pp AND pd INTERACTIONS

Abstract

The K+-production cross section in pn collisions is an important input parameter for model calculations of K+ production in proton-nucleus and nucleus-nucleus interactions. Experimental data in the close-to-threshold region are not yet available and theoretical predictions give a wide scatter of numbers for the ratio of the total cross sections [Formula: see text]. K+ production from pd interaction has been investigated using the magnetic spectrometer ANKE at COSY-Jülich at proton beam momenta 2.65, 2.81 and 3.46 GeV/c. For the extraction of [Formula: see text] from the pd data at low beam momenta, a naive phase-space approach has been used, assuming that [Formula: see text]. Double differential cross sections and missing mass spectra for proton-kaon correlations have also been analysed. Both methods give consistent result: [Formula: see text]. During a recent beam time, experimental data have been collected at pp=3.46 GeV/c for both hydrogen and deuterium targets. A ratio [Formula: see text] has been extracted from these data.