Systematic experimental evidence is presented for the decay of nuclear matter from toroidal geometries using reactions of ${}^{86}\mathrm{Kr}{+}^{93}\mathrm{Nb}$ at incident energies ranging from 35 to 95 MeV/nucleon. The decay of noncompact geometries is established through two charge-related observables, and the distinction between toroidal and bubblelike geometries is achieved through event shape analysis. Indications of these exotic geometries appear for beam energies between 60 and 75 MeV/nucleon.

• Received 23 July 1996

DOI:https://doi.org/10.1103/PhysRevLett.78.2084