A pop-out plasma phalanx mounting on a Q-Ship.
A Plama Phalanx is a small or medium-sized plasma-based weapon, used on small starships as a point defense weapon against incoming projectiles, or on large ground vehicles (such as hovertanks or RABBIT artillery) and military base facilities as a combination point-defense mount/heavy antipersonnel weapon. It generally consists of two or more Plasma Cannons on a turret mounting, along with attached targeting sensors. Since it does not require a large dedicated linear particle accelerator to feed it, it can be mounted on much smaller vessels (as small as corvettes, or frigates, or even large freighters) than a full Particle Phalanx (which can only be mounted on warships destroyer-sized or larger), although the charged plasma is much less effective against shielded targets than the antineutron beam of a Particle Phalanx.