Pulsed energy projectile or PEP is a technology of non-lethal weaponry currently under development by the U.S. military. It involves the emission of an invisible laser pulse which, upon contact with the target, ablates the surface and creates a small amount of exploding plasma. This produces a pressure wave that stuns the target and knocks them off their feet, and electromagnetic radiation that affects nerve cells causing a painful sensation. The technology can also be used as a lethal weapon, and indeed an early name was pulsed impulsive kill laser.
The pulsed energy projectile is intended for riot control and is said to work over distances of up to 2 km. It weighs about 230 kg and will probably be mounted on vehicles. The weight could become lighter as laser production technology improves.
The system was developed by Mission Research Corporation (now owned by Orbital ATK). It uses a chemical deuterium fluoride laser device producing infrared laser pulses. The plasma (produced by the early part of the pulse) explodes because its electrons absorb the energy of the later part of the pulse.
In 2003, a US military review reported that the electromagnetic radiation produced by PEPs had been shown to cause pain and temporary paralysis in animal experiments.
United States Special Operations Command FY 2010 plans included starting developmental work on a Counter UAV Pulsed Energy Projectile.