Evidence for a new state produced in antiproton annihilations at rest in liquid deuterium

Inclusive charged-pion spectra from p¯d annihilations at rest have been measured in a high-statistics experiment in search of broad states. Analysis of these spectra reveals an enhancement of the ${\pi }^{\mathrm{-}}$ spectrum at 315 MeV/c. This may be interpreted as a production of a new state of mass 1485 MeV/$c^2$ and width at most 200 MeV/$c^2$ recoiling against the ${\pi }^{\mathrm{-}}$. This quasi two-body final state accounts for a large fraction of the p¯n annihilations.