The $pd{\to }^3{H}_{\Lambda }{K}^{+}$ reaction cross section

Abstract

The one- and two-step mechanisms of the $pd{\to }^3{H}_{\Lambda }{K}^{+}$ 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 ${}^3{H}_{\Lambda }$ 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.

Comments: 10 pages, Latex, 3 Postscript figures