Potential structure modified by electron cyclotron resonance in a plasma flow along magnetic field lines with mirror configuration

A plasma potential structure is modified by the electron cyclotron resonance (ECR) in a collisionless plasma flow along magnetic field lines with simple mirror configuration. In the presence of a single ECR point at the bottom of the magnetic well, there appears a potential dip (thermal barrier) around this point, being followed by a potential hump (plug potential) in the downstream side. The result in this simplified configuration gives a clear-cut physics to the formation of field-aligned plug potential with thermal barrier.