Diagnostics and modelling of noble gas atmospheric pressure dielectric barrier discharges in homogeneous or diverging electric fields

We present experimental results of 'atmospheric pressure glow discharges' in two different electrode configurations, plane–plane and cylinder–plane. Although many of the phenomena we report here have been observed in different noble gases, we restrict this presentation primarily to the case of helium. Discharge diagnostics have been carried out using ultra-high speed imaging, and synchronous detection of light emission and current–voltage measurements, the former using a photomultiplier. The discharge physics is discussed with reference to recent work reported by the present authors and others.