The tributary beam was a component of the Death Star I's superlaser that was assembled at Desolation Station.
The tributary beam was initially created for Project Hammertong, although the Death Star eventually superseded it. One prototype was stolen before it could be delivered to the Death Star by X2, who also destroyed the station. However, another version of the beam was eventually installed aboard the station, with eight being used for the circumference of the superlaser.
The tributary beam started with a principle energy inducer, followed by rows of primary focusing coils, eventually connecting gravitational flux dampeners (which were necessary for lowering the gravitational flux that would have otherwise posed a grave risk to the battle station). The amplification crystal chamber was directly connected to the dampeners, and then followed by a long column of galven coils before meeting up with the Collimator. The pulse capacitor connected the collimator with the three magnetic dissipators (necessary for lowering the risk of magnetics destroying the battle station), as well as fine targeting coils at the center.
Imperial gunners who operated the tributary beams wore helmets similar to the Imperial Navy Death Star Troopers due to requiring direct audio communication with fellow gunners due to static charges from the tributary beam otherwise disabling comm links.