Two-color Mie-scattering images of uncorrelated and correlated trapped dust in low-frequency helium discharges

Simultaneous two-color Mie scattering images from the particle size dependent self-assembled trapped dust particles in a low-frequency helium discharge have been measured. The dynamics of the dust ensemble during the discharge switch-off suggests that the long range order in a correlated dust phase can reduce the ion-ion and the electron-ion recombination rates on dust surface by several orders of magnitudes compared to the ambipolar or to free diffusion rates.