GENERATION OF UNIFORMLY SIZED, CHARGED-PARTICLES IN A VACUUM

An experimental technique that uses a modified vibrating orifice aerosol generator has been developed for the continuous generation of monodisperse, charged particles in subatmospheric pressure. The technique achieves well-defined control of charge of either polarity by induction charging of the uniformly sized particles produced by the aerosol generator. Particle charge was measured by the collection of particles in a Faraday cup connected to a microammeter. The size and morphology of the particles generated by this device were investigated by using optical and scanning electron microscopy. The performance of the vibrating orifice aerosol generator with and without the use of the conventional syringe pump was investigated for vacuum operation. The technique is found to be a useful method to generate charged aerosol particles for the study of aerosol behavior in vacuum conditions.