Two Hyperfragments from Negative<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>K</mml:mi></mml:math>-Particle Capture and the Mass of the Negative<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>K</mml:mi></mml:math>Particle

Abstract

Two hyperfragments are described which have been found from 81 negative $K$-particle interactions at rest and in flight. Event 35 was identified as a ${K}^{\ensuremath{-}}$ capture in carbon which emitted a $_{\ensuremath{\Lambda}}\mathrm{Li}^{7}$ hyperfragment that decayed into a ${\ensuremath{\pi}}^{\ensuremath{-}}$ meson and a ${\mathrm{Be}}^{7}$ fragment. The binding energy of the $\ensuremath{\Lambda}$ hyperon in $_{\ensuremath{\Lambda}}\mathrm{Li}^{7}$ was found to be 4.4\ifmmode\pm\else\textpm\fi{}0.7 Mev. The mass of the negative $K$ particle which was captured in this reaction was found to be 966.2\ifmmode\pm\else\textpm\fi{}5.0 electron masses. In Event 71, a negative $K$ particle was captured in a light nucleus. Four charged particles and a ${\ensuremath{\pi}}^{\ensuremath{-}}$ meson and a hyperfragment, $_{\ensuremath{\Lambda}}\mathrm{He}^{4}$, left the ${K}^{\ensuremath{-}}$ ending. The $_{\ensuremath{\Lambda}}\mathrm{He}^{4}$ decayed into a proton, a ${\ensuremath{\pi}}^{\ensuremath{-}}$ meson, and a ${\mathrm{He}}^{3}$ fragment. The binding energy of the $\ensuremath{\Lambda}$ hyperon in $_{\ensuremath{\Lambda}}\mathrm{He}^{4}$ was found to be 1.5\ifmmode\pm\else\textpm\fi{}0.6 Mev.