Background:

The magnetic constrictors make up the bulk of the warp core. They provide physical support to the reaction chamber, pressure containment for the whole core and, most importantly, guide and align the fuel flow onto the desired location within the reaction chamber.

The matter constrictor is typically longer than the antimatter constrictor, as antimatter is easier to focus and so requires a shorter distance for the same accuracy. Typically, the magnetic constrictors are divided into segments; each segment will contain several sets of tension frame members, a toroidal pressure vessel wall, several sets of magnetic constrictor coils and related power and control hardware. Constrictor coils will have dozens of active elements, and on more advanced designs these will be configures to contain the magnetic field almost wholly within the constrictor, with minimum spillage into the exterior environment. UFED warp cores usually have the outermost layers of the constrictors constructed of a semi-transparent layer, which allows harmless secondary photons to escape from the inner layers, creating a glow effect. This gives an immediate visual cue to the current activity rates within the warp core

As the fuel is released from the injector nozzles, the constrictors compress it and increase the velocity considerably. This ensures the proper collision energy and alignment within the reaction chamber.