Nuclear Reaction Times in the Deep-Inelastic U + U Collision Deduced from<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>K</mml:mi></mml:math>-Shell Ionization Probabilities

Abstract

The $K$-shell ionization probability ${P}_{K}$ of the uraniumlike products has been measured in the deep-inelastic reaction U + U at a beam energy of 7.5 MeV/u as a function of the total kinetic energy loss $\ensuremath{-}Q$. ${P}_{K}$ was determined for $Q$ values down to - 190 MeV. After the subtraction of the ionization induced by internal conversion of $\ensuremath{\gamma}$ rays, a strongly $Q$- dependent ${P}_{K}$ is found in qualitative agreement with theoretical predictions. From the data we infer a nuclear reaction time of approximately ${10}^{\ensuremath{-}21}$ s at $Q=\ensuremath{-}100$ MeV.