The Phased Plasma Gun (or PPG) is a fictional weapon from the television series Babylon 5. It fires a small charge of superheated helium. This helium plasma retains both its shape and small volume via a residual magnetic field. Upon impact with an object, the magnetic field is dissipated and the heat discharged. PPG bolts cause significant visible distortion as they travel through air.
The PPG is composed only of highly heat-resistant alloys, due to the rapid and extreme heating and cooling that it must endure during regular use. One of these alloys is morbidium. A line in the Babylon 5 episode "Chrysalis" states that it is a metal that is harder than diamond. The electromagnetic firing coil is composed of morbidium, and has the gun's serial number printed on it, so that PPGs are just as traceable as modern guns. PPGs make a distinctive charging sound when they are armed for firing, and they are powered by compact energy sources called energy caps. Two models are most commonly seen in the series: a handgun-type that is the standard EarthForce sidearm, and a more-powerful assault-rifle-type used by security personnel in emergencies.
Even though PPGs are more expensive to produce than normal projectile weapons ("slug-throwers"), they are the standard-issue military sidearm for space-based personnel. While a stray bullet from a normal weapon can puncture the hull of a spacecraft or space station, causing unintended decompression, a PPG cannot penetrate most heavy bulkheads. A PPG shot may, however, burn through some materials. In several episodes, PPG shots were fired through the thin walls of air ducts in order to attack people inside.
In earlier episodes, where few shots were fired, plasma bursts were carefully generated and penetrated their targets. Later in Babylon 5, when massive battles were staged, a shift into a lower quality CGI followed and the bursts tended to fade off as opposed to continuing through its target.
The Phased Plasma Gun (or PPG) was available in various configurations. The Standard PPG was seen during the original series. The Assassins PPG was also seen during the original series. The Crusade version was seen in Bayblon 5's spin-off Crusade.
In the film The Terminator, the eponymous character played by Arnold Schwarzenegger goes to a gun shop in 1984 Los Angeles and requests a "phased-plasma rifle in the 40-watt range," a weapon from its own time which can be seen being used by resistance fighters and terminators alike during the film's scenes of post "Judgment Day" conflict.
In Aliens, another film by James Cameron, a "phased-plasma pulse rifle" is a weapon that the excitable Private William Hudson (Played by Bill Paxton), jokingly informs Ripley is part of the Marines arsenal (along with knives and sharp sticks). The scene takes place aboard the marine dropship and was omitted from the original version released to theaters. It can been seen in the film's Special Edition, which was first released in 1992 and then later in subsequent DVD box sets.
In the online role-playing game, EVE Online, "Phased Plasma" is a type of ammunition for projectile weapons (firearms) that does considerable thermal-type damage and some kinetic-type damage, described as an equivalent of the particle beam "blaster" built into a conventional artillery round.