We have studied the $S^{*}$ meson using data from the reactions ${\pi }^{-}p\to {\pi }^{+}{\pi }^{-}n$ and ${\pi }^{-}p\to {\mathrm{K}}^{+}{\mathrm{K}}^{-}n$ at 1980 MeV/c. The parameters of the $S^{*}$ pole were found by fitting the dimeson mass spectra from these reactions to a Breit-Wigner resonance formula with a coherent background. The dimeson mass was calculated from the beam and neutron four-vectors, the latter being measured by a time-of-flight technique. The mass resolution is $\sigma =4\mathrm{}$ MeV/${\mathit{c}}^2$. Dimeson production was identified by analyzing the final-state meson trajectories with a magnetostrictive wire spark-chamber spectrometer. The events in our data sample were required to have a slow forward-going neutron which restricted the allowed range of four-momentum transfers to $|t-t_{min}|<\mathrm{}0.003\mathrm{}$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ in the $S^{*}$ region. From a sample of 21 700 ${\pi }^{+}{\pi }^{-}n$ events and 52 $K^{+}{K}^{-}n$ events, we find the position of the $S^{*}$ pole to be $(970\mathrm{}\pm 5)-i(22\pm 5)$ MeV/${\mathit{c}}^2$ as compared to the present world average value of $(993\mathrm{}\pm 4)-i(20\pm 4)$ MeV/${\mathit{c}}^2$.

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