What powerful, collimated outflows erupt perpendicular to the accretion disk during accretion?

Bipolar jets

As matter swirls onto the forming protostar via the accretion disk, the system must manage the angular momentum carried by that infalling material. The extreme conditions near the rapidly spinning protostar and disk lead to the violent expulsion of matter in highly focused streams known as bipolar jets. These jets erupt perpendicularly, or perpendicular, to the plane of the accretion disk, blasting away surrounding gas. Crucially, these jets serve a vital role in the star formation process: they carry away the excess angular momentum from the system. Without this mechanism to shed angular momentum, the material would pile up indefinitely in the disk, preventing further matter from settling onto the central protostar.