The $pd\to ^3H_\Lambda K^+$ reaction cross section

Abstract

The one- and two-step mechanisms of the $pd\to ^3H_\Lambda K^+$ reaction in the range of incident proton kinetic energy 1.13-3.0 GeV have been investigated. A remarkable peculiarity of the two-step mechanism which incorporates subprocesses $pp\to d\pi ^+$ and $\pi^+n\to K^+\Lambda $ is the so called velocity matching providing the presence of all intermediate particles nearly to the on-mass-shell. The differential cross section has been calculated using a realistic model for the hypertritium $^3H_\Lambda $ wave function. The maximum value of the cross section is estimated as $\sim $1nb/sr. The contribution of the one-step mechanism with the elementary process $pN\to NK\Lambda $ into the cross section has been found to be two - three orders of magnitude smaller in comparison with the two-step mechanism.