Clear evidence for a positive correlation is established between the
magnitude of magnetic fluctuations in the lower-hybrid frequency range and
enhancement of reconnection rates in a well-controlled laboratory plasma. The
fluctuations belong to the right-hand polarized whistler wave branch,
propagating obliquely to the reconnecting magnetic field, with a phase velocity
comparable to the relative drift velocity between electrons and ions. The short
coherence length and large variation along the propagation direction indicate
their strongly nonlinear nature in three dimensions.Comment: 4 pages, 6 figures, submitted to Phys. Rev. Let