Context: In The Future, a beautiful astronomatrix named Barbarella (Jane Fonda) floats through the galaxy in her spaceship, the Alpha-7. Suddenly she receives an urgent call on her monitor from none other than the President of Earth (Claude Dauphin). He informs her that a young scientist named Durand-Durand went missing sometime during a mission to the North Star and is believed to have landed somewhere in the Tau Ceti star system. Not much is known about this region of space-- the President worries that Durand's invention, the positronic ray, may fall into the hands of a primitive culture; beings who might seek to use this technology as a weapon and launch an intergalactic war. Since the Earth, free of all conflict for centuries, lacks military and police personnel, the President tasks Barbarella with a mission to find the scientist. He teleports her some weapons and a device that will signal the presence of Durand-Durand. The latter has a "tonguebox" incorporated in its design which can translate any language.Barbarella spends most of the journey to Tau Ceti in suspended animation. She awakens just in time to lose control of her spacecraft and crash land on Planet 16, which her spaceship informs her contains an atmosphere similar to Earth's. She changes into a new outfit to explore the arctic terrain. The first humanoids she meets are a pair of twin girls-- they jabber to her excitedly in a language she can't understand. Before she can adjust her tonguebox, one of them knocks Barbarella unconscious with a piece of ice. The girls then pull the dazed explorer along in their sled, which is attached to a manta ray-like creature that glides across the ice.The girls arrive with Barbarella at the wreck of another craft where several other sets of twin children are sheltered and indigo-blue bunny rabbits abound. Barbarella recognizes the wreck as the Alpha-1, former spaceship of Durand-Durand. The children tie Barbarella to a post and bring out several mechanical dolls that walk towards her. It soon becomes apparent that the dolls all have sharp metal teeth and hinged jaws. They bite Barbarella while the children giggle gleefully, amused by their game.Suddenly a man appears with several armored guards. He cracks a whip and captures the children in a net, then unties Barbarella. Once she gets her tonguebox working, she's able to understand him when he explains that he is a Catchman named Mark Hand (Ugo Tognazzi) and that all children are sent away to the forests of Weir "until they've reached a serviceable age," at which point he captures them and brings them back to civilization. He offers Barbarella a ride back to her spaceship. When she asks how she can repay him, he tells her that he'd like to make love to her. Back on Earth, when people want to bond, erotically, they each take an exultation transference pill and press their palms against one another's. Barbarella is prepared to do this with the Catchman, but he's not interested in all that, he tells Barbarella that he wants to have sex on the bed in his snowship. She reluctantly agrees to do it the old-fashioned way, but soon discovers that she finds the experience quite enjoyable. The Catchman gives her a fur and repairs her spaceship, only when she tries to fly off, the ship's computer informs her that it's been repaired in reverse. She crashes back into the planet and quickly activates the ship's terra-screws so that she can tunnel through the planet's core.She surfaces in the Labyrinth, amongst strange creatures including an "ornithanthrope," or angel, named Pygar (John Phillip Law), who was blinded in the city of Sogo. Pygar takes Barbarella to visit Professor Ping (Marcel Marceau) who explains that Pygar is aerodynamically sound, but lacks the morale to fly. Pygar, Professor Ping and all of the other unfortunates who roam the Labyrinth were imprisoned there by order of the Great Tyrant. They are not evil enough to be allowed to live in Sogo, the City of Night. Pygar takes Barbarella to his nest where they have sex. This restores Pygar's will to fly and Barbarella 
 Question: What does Durand Durand use to decimate the rebels?
Output: positronic ray