No abstract

The correlation pattern in the center of mass motion of the three fragments from dissociation of well-defined Rydberg states of H 3 and D 3 is studied. Dissociation of the molecules is induced by an external electric field. Through a comparison with results obtained in radiative cascading we can show that the correlation pattern is that of the short-lived 2s 2 A 1 electronic state, of which a tiny amplitude is admixed by the external electric field. A comparison of our results with the predictions by M. Lehner and M. Jungen [J. Phys. B 42, 065101 (2009)] and U. Galster [Phys. Rev. A 81, 032517 (2010)] for predissociation of the 2s 2 A 1 state is made. We show that the experimental vector correlation maps are direct images of the spatial symmetry of the product of the vibrational wave function and spatial dependence of the nonadiabatic coupling operator.

The equivalence of a complete characterization of linear momenta of fragments from a many-body fragmentation process and the spatial wave function of the many-body system is discussed. Our experiment on three-body dissociation of state selected H3 and D3 molecules into ground-state hydrogen atoms strongly suggests the existence of such a close relationship as it is also predicted by theory in the form of the imaging theorem. We conclude that prudent imaging of many-body fragmentation provides a laboratory view of the squared many-body wave function at a spatial scale of molecular dimensions at which fragments exit into the realm of independent free particles.

Three-particle dissociation of high-lying Rydberg states of D3 is induced by an external electric field. We observe that the momentum vector correlation map of the center-of-mass motion of the fragments converges near the ionization threshold to two distinct fragment configurations, the near linear geometry and the symmetric acute angle geometry. A comparison is made with the momentum vector correlation map recorded in dissociative recombination of D3(+) with slow electrons and with the corresponding results for H3 where the acute angle geometry is conspicuously absent.