Omega reactor
From FEInfobase
A chemical reactor, designed to synthesize Omega molecules from raw boronite ore. The Omega reactor is utilized only after General order 22 is given. Omega reactors were installed on select capital ships and Starfleet space stations in the 2390's as a last resort weapon to stop the Borg. Once it was determined a Borg force would overwhelm a Starfleet installation or defense line the new Omega Directive would be activated. Upon receipt of the directive the ship or installation with the reactor would immediately initialize start up. 22 seconds after the initial start a massive Omega particle chain reaction would be initiated, causing massive sector-wide - if not quadrant-wide - disruptions in subspace, thus effectively stopping all warp and transwarp travel into and out of the area. As of 2404 the new Omega Directive has never been issued. The only known solution to Omega's effects on FTL travel in an affected area is the newly developed quantum slipstream drive.
In early 2405, it was believed an Omega reaction was responsible for the massive subspace disruptions in and around the Talosian system. This is currently being investigated.