Proton Pack - in The Ghostbusters Universe

In The Ghostbusters Universe

The Proton Pack, designed by Dr. Egon Spengler, is a man-portable particle accelerator system that is used to create a charged particle beam - composed of protons - that is fired by the proton gun (also referred to as the "neutrona wand"). Described in the first movie as a "positron collider", it presumably functions by colliding high-energy positrons to generate its proton beam. The beam allows a ghostbuster to contain and hold "negatively charged ectoplasmic entities". This containment ability allows the wielder to position a ghost above a trap for capture. The name "Proton Pack" was not used until the subway tunnel scene in Ghostbusters 2 when Egon says that they should get their proton packs. The doorman to the Mayor's mansion also uses the term "proton pack" as a toy for his little brother. Egon then replies that "A Proton Pack is not a toy."

While the Ghostbusters' dialogue indicates that the accelerator system operates similarly to a cyclotron (and indeed Dr. Peter Venkman refers to the Proton Packs in one scene as "unlicensed nuclear accelerators"), modern particle accelerators produce well collimated particle beams. This is far different from the beam from a Proton Pack, which tends to undulate wildly (though it still stays within the general area at which the user is aiming). The proton stream is quite destructive to physical objects, and can cause extensive property damage.

In the 2009 Ghostbusters game, Ray explains how the Proton Pack works early in the game; the energy emitted by the Proton Stream helps to dissipate psychokinetic (PK) energy which ghosts use to manifest themselves. Draining them of their PK energy weakens them, allowing them to be captured in their portable ghost traps.

According to a line spoken by Egon in Ghostbusters II, each pack's energy cell has a half-life of 5,000 years. Knobs on the main stock of the Proton Pack can perform various functions to customize the proton stream, including adjustments for stream intensity, length, and degrees of polarization. In the cartoon series, The Real Ghostbusters, the maximum power setting for the Proton Packs is "500,000 MHz," which possibly refers to the rate of positron collisions occurring within the pack's accelerator system. In the cartoon the packs also have a self-destruct mechanism capable of affecting at least a half-mile radius. The Real Ghostbusters and the Extreme Ghostbusters also made proton packs less efficient with power cells, allowing them to run out of energy when appropriate for dramatic tension, the latter needing replaceable cartridges.

The IDW monthly Ghostbusters Comic storyline has shown the movie pack, a boson dart capable pack and the Extreme Ghostbusters pack in use. The IDW Comic also shows a proton pistol attachment to the movie pack being used by Winston while hunting down Slimer.