  Spontaneous avalanche to plasma splits the core of an ellipsoidal Rydberg gas
of nitric oxide. Ambipolar expansion first quenches the electron temperature of
this core plasma. Then, long-range, resonant charge transfer from ballistic
ions to frozen Rydberg molecules in the wings of the ellipsoid quenches the
centre-of-mass ion/Rydberg molecule velocity distribution. This sequence of
steps gives rise to a remarkable mechanics of self-assembly, in which the
kinetic energy of initially formed hot electrons and ions drives an observed
separation of plasma volumes. These dynamics adiabatically sequester energy in
a reservoir of mass transport, starting a process that anneals separating
volumes to form an apparent glass of strongly coupled ions and electrons.
Short-time electron spectroscopy provides experimental evidence for complete
ionization. The long lifetime of this system, particularly its stability with
respect to recombination and neutral dissociation, suggests that this
transformation affords a robust state of arrested relaxation, far from thermal
equilibrium.
