Characterisation of plasmas created in conducting liquids

Summary form only given. There are many current and potential applications for plasmas created in conducting liquids and particularly in isotonic saline solution. As a result there is interest in the physics of the plasma production, how it is sustained, the type of plasmas produced, their parameters and the subsequent plasma produced chemistry. There have been a number of studies of various topics in this list however the full characterisation of the plasma has been hampered since the plasma formation process is not reproducible and many conventional plasma diagnostic techniques cannot, as yet, be applied in the liquid environment. Here we report approaches to making the plasma formation more reproducible and to the application of new diagnostics. We do this using a system for which the process of vapour layer formation has previously been described in detail as well as electron density measurements having been performed. Here we will present fast camera measurements from two cameras used without filters and with independently varied time delays to examine the evolution of the discharge structure. In addition the feasibility of determining the discharge electron temperature using emission intensity line ratios from excited states of Barium will be discussed along with a investigation of the substitution of the NaCl salt with BaCl₂ on the discharge behaviour .