General Bohm and Langmuir Conditions for a Strong Double Layer in Space Plasmas

We investigate the general Bohm and Langmuir conditions for a strong double layer and show that in some cases these do not necessarily imply a net current through the double layer as is now the popular belief. We demonstrate this by deriving the appropriate Bohm and Langmuir conditions when there are three beam-type particles passing through the double layer in addition to the usual two species of trapped particles.