Shot noise control and reduction by collective coulomb interactions: 3D simulations evidence

We present 3D simulations that verify a predicted current shot noise suppression effect. It was verified numerically that minimal current shot-noise is attainable in a drift length of quarter wavelength plasma oscillation as predicted by the 1D single mode model. We identify the parameter range, in which 3D deterioration effects are avoided, and the single mode model is valid. The noise reduction process may be applicable for controlling micro-bunching instabilities as well as enhancement of free electron laser coherence below the classical shot noise level.