The proton pack is a fictional energy-based capture device, used for controlling and lassoing ghosts in the Ghostbusters universe. First depicted in the film Ghostbusters, it has a hand-held wand ("Neutrona Wand" or particle thrower) connected to a backpack-sized nuclear accelerator. It controls a stream of highly focused and radially polarized protons that electrostatically controls the negatively charged energy of a ghost, allowing it to be held in the stream.
In the Ghostbusters universe
thumb|upright|left|A replica of the ghost trap used in the original film
The proton pack, designed and built by Dr. Egon Spengler, is a man-portable cyclotron system (and indeed Dr. Peter Venkman refers to the proton packs in one scene as "unlicensed nuclear accelerators"), The stream is also 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 also made proton packs less efficient with power cells, allowing them to run out of energy when appropriate for dramatic tension.
For the 1997 animated spinoff Extreme Ghostbusters, the proton packs and ghost traps are redesigned to combat the threat of the malevolent Achira, an ancient disease-provoking entity accidentally released by workers constructing a new subway tunnel. Egon, with the help of Roland, Kylie and Eduardo, increased the proton packs' nuclear capability (to deal with Achira and other subsequent enemies, much stronger than what the original Ghostbusters had faced) and modified the power system; now, the packs required replaceable proton canisters to be loaded in for them to function. The trap was redesigned as well, into a gold-colored, round-shaped device with an opening hatch atop it. Kylie would typically carry it; due to this, she did not carry a normal proton pack, instead carrying a not-as-powerful proton pistol.
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.
Crossing the streams
Crossing the streams was initially discouraged, as Egon believed that "total protonic reversal" would occur: this effect would have catastrophic results (see quote above) if they are crossed over three seconds. However, in a desperate effort to stop the powerful Gozer the Gozerian, Egon noted that the door to Gozer's temple "swings both ways" and that by crossing the streams, they may be able to create enough force to close the door on Gozer and its control. As the Ghostbusters cross the streams, the combination of that much energy closes the door to Gozer's dimension and severs its ties to our world. The resulting blast destroys a good portion of the roof and blows up the Stay Puft Marshmallow Man.
Toy proton packs were formerly made by Kenner as part of the Real Ghostbusters toy line. They consisted of a plastic hollow pack and gun, with a yellow foam cylinder attached to the front of the gun to represent the beam.
In late 2021, Hasbro announced a 1:1 scale replica of Spengler's Proton Pack as a Haslab crowdfunding campaign, with preorders opening in late October 2021. The project was successfully backed by the deadline and was put into production, with the first shipping in January 2023.
References
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