Photo- and Electroproduction of the Hypertriton on 3He

TL;DR

This study calculates differential cross sections for hypertriton photo- and electroproduction on 3He, emphasizing the importance of Fermi motion treatment and off-shell assumptions, and compares theoretical predictions with experimental data.

Contribution

It introduces a detailed analysis of Fermi motion effects and off-shell assumptions in hypertriton production, using modern nuclear wave functions and the KAON-MAID operator.

Findings

Proper Fermi motion treatment is crucial for accurate cross sections.

Off-shell assumptions significantly affect electroproduction results.

The D_{13}(1895) resonance greatly influences longitudinal cross sections.

Abstract

Differential cross sections of the photo- and electroproduction of the hypertriton have been calculated by utilizing modern nuclear wave functions and the elementary operator of KAON-MAID. It is found that a proper treatment of Fermi motion is essential for the two processes. While the average momentum approximation can partly simulate the Fermi motion in the process, the ``frozen nucleon'' assumption yields very different results, especially at lower energies. The Coulomb effect induced by the interaction between the positively charged kaon and the hypertriton is found to be negligible. The influence of higher partial waves is also found to be relatively small, in contrast to the finding of the previous work. The off-shell assumption is found to be very sensitive in the case of electroproduction rather than in photoproduction. It is shown that the few available experimental data favor the assumption that the initial nucleon is off-shell and the final hyperon is on-shell. This seems to be reasonable, since the hyperon in the hypertriton is less bound than the nucleon in the initial 3He nucleus. The effect of the missing resonance D_{13}(1895) is more profound in the longitudinal cross sections. Excluding this resonance reduces the longitudinal cross sections by one order of magnitude, but does not change the effects of various off-shell assumptions on the cross sections.