  Coronal jets and bright points occur prolifically in predominantly unipolar
magnetic regions, such as coronal holes, where they appear above
minority-polarity intrusions. Intermittent low-level reconnection and
explosive, high-energy-release reconnection above these intrusions are thought
to generate bright points and jets, respectively. The magnetic field above the
intrusions possesses a spine-fan topology with a coronal null point. The
movement of magnetic flux by surface convection adds free energy to this field,
forming current sheets and inducing reconnection. We conducted
three-dimensional magnetohydrodynamic simulations of moving magnetic elements
as a model for coronal jets and bright points. A single minority-polarity
concentration was subjected to three different experiments: a large-scale
surface flow that sheared part of the separatrix surface only, a large-scale
surface flow that also sheared part of the polarity inversion line surrounding
the minority flux, and the latter flow setup plus a "fly-by" of a
majority-polarity concentration past the moving minority-polarity element. We
found that different bright-point morphologies, from simple loops to sigmoids,
were created. When only the field near the separatrix was sheared, steady
interchange reconnection modulated by quasi-periodic, low-intensity bursts of
reconnection occurred, suggestive of a bright point with periodically varying
intensity. When the field near the PIL was strongly sheared, on the other hand,
filament channels repeatedly formed and erupted via the breakout mechanism,
explosively increasing the interchange reconnection and generating non-helical
jets. The fly-by produced even more energetic and explosive jets. Our results
explain several key aspects of coronal-hole bright points and jets, and the
relationships between them.
