A measurement of the total cross-sections for $\Lambda$ hyperon interactions on protons and neutrons in the momentum range from 6 GeV /c to 21 GeV/c

The Lambda p, Lambda n, Lambda p, and Lambda n total cross-sections were measured in the Lambda momentum interval 6-21 GeV/c. Within the experimental uncertainties the cross-sections are momentum-independent in this interval and the momentum-averaged cross-sections are found to be: sigma ( Lambda p)=34.6+or-0.4 mb; sigma ( Lambda n)=34.0+or-0.8 mb; sigma ( Lambda p)=56+or- 11mb; sigma ( Lambda n)=46+or-20 mb. The first two results are in agreement with charge symmetry, and with simple quark model sum rules applied to previous results on pp, K/sup -/n, and pi /sup +/p total cross-sections. (14 refs).