Efficiency of Magnetic to Kinetic Energy Conversion in a Monopole Magnetosphere

Understand

Unconfined relativistic outflows from rotating, magnetized compact objects are often well-modeled by assuming the field geometry is approximately a split-monopole at large radii.

• Earlier work has indicated that such an unconfined flow has an inefficient conversion of magnetic energy to kinetic energy.
• This has led to the conclusion that ideal magnetohydrodynamical (MHD) processes fail to explain observations of, e.g., the Crab pulsar wind at large radii where energy conversion appears efficient.
• In addition, as a model for astrophysical jets, the monopole field geometry has been abandoned in favor of externally confined jets since the latter appeared to be generically more efficient jet accelerators.