Highlights of the reaction ${\pi }^{-}p\to {\pi }^{-}{\pi }^{+}n$ at 100 and 175 GeV/c

We present a summary of the physics results from an experimental study of the reaction ${\pi }^{-}p\to {\pi }^{-}{\pi }^{+}n$ at 100 and 175 GeV/c incident-beam momentum. Our data show the continuing dominance of one-pion exchange in these reactions with the characteristic $\frac{1}{{P_{\mathrm{lab}}}^2}$ momentum dependence. We extract the pion Regge trajectory from our data on ${\pi }^{-}p\to {\rho }^{0}n$ and study the zero structure of the $\pi \pi$ differential cross section up to $s_{\pi \pi }=12\mathrm{}$ ${\mathrm{GeV}}^2$.