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An edge-confined single-species plasma will relax to create a potential energy hill that climbs from the boundary. This hill represents a potential well for species of the opposite sign and can be a means to confine the second species. With this ultimate application in mind, we have studied the relation between the plasma temperature, the number of confined particles, and the electrostatic potential well that forms in a fully non-neutral plasma of electrons in a trapping volume with an artificially structured boundary (ASB). An ASB is a structure that produces periodic short-range static electric and magnetic fields for confining a plasma. To perform a detailed analysis on this topic, simulations using a particle-in-cell code have been performed. By varying the configurational elements of the ASB, such as the bias on the boundary electrodes and the internal radius of the structure, coupled with a course thermalization process and a prescribed threshold for particle leakage, potential well values were determined for a range of plasma temperatures and confinement conditions. Maximum well depths were observed below a threshold plasma temperature in each configuration. This study gives insight into the limitations of primary particle confinement with this type of structure and optimal conditions for the formation of a potential well that might be utilized to confine a second species. 

A model for plasma confinement is developed and applied for describing an electrically confined thermonuclear plasma. The plasma confinement model includes both an analytical approach that excludes space charge effects and a classical trajectory Monte Carlo simulation that accounts for space charge. The plasma consists of reactant ions that form a non-neutral plasma without electrons. The plasma drifts around a negatively charged electrode. Conditions are predicted for confining a deuterium–tritium plasma using a 460 kV applied electric potential difference. The ion plasma would have a 20 keV temperature, a 1020 m−3 peak density, and a 110 keV average kinetic energy per ion (including drift and thermal portions at a certain point in the plasma). The fusion energy production rate is predicted to be 10 times larger than the energy loss rate, including contributions associated with both plasma loss to electrodes and secondary electron emission. However, an approach for enhancing the fusion power density may have to be employed to realize a practical use for centrifugal-electrostatic confinement fusion. 

Antihydrogen formation involving magnetobound positronium is simulated by computing classical trajectories. Simulated collisions between electrons and positrons generate magnetobound positronium, which consists of electron–positron pairs that are not energetically bound but that have spatially correlated trajectories within a magnetic field. Simulations show that antihydrogen can form if such electron–positron pairs pass near antiprotons. In addition, the possibility of forming antihydrogen atomic ions or antihydrogen molecular ions via magnetobound positronium or magnetobound antihydrogen is discussed. 

A summary of closed-form expressions for the magnetic fields produced by rectangular- and circular-shaped finite-length solenoids and current loops is provided altogether for easy reference. Each expression provides the magnetic field in all space, except locations where a current of infinitesimal thickness is considered to exist. The closed-form expression for the magnetic field of a rectangular-shaped finite-length solenoid is derived using the Biot–Savart law. Closed-form expressions for the magnetic fields of solenoids and current loops can be used to avoid approximations in analytical models and may reduce computation time in computer simulations. 

The possibility of fueling a magnetically confined plasma using particle sources located inside of the plasma is studied by computer simulation. Magnetic plasma expulsion [R. E. Phillips and C. A. Ordonez, Phys. Plasmas 25, 012508 (2018)] would serve to keep the magnetically confined plasma away from the particle sources without adversely affecting plasma confinement. The simulations show how charged particles can be injected into a plasma by using particle sources located directly between two current-carrying wires that create a magnetic expulsion field. Plasma fueling with the average energy of injected particles greater than the average energy of plasma particles may serve for heating the plasma. Also, plasma fueling with positive and negative particles injected at different rates may serve for changing the neutrality of the plasma. Conditions for plasma fueling are investigated using a classical trajectory Monte Carlo simulation. Two types of particle sources are considered, and the fraction of emitted particles that reach (and fuel) the magnetically confined plasma is evaluated for each.