I had a rethink on the suggestion on naming above, taking away the real world science elements, a few came up like this.
Blaster: Pulsing 'laser'. I'm a bit hesitant to call them blasters though.
Pulse (Gun): Energy needle rapid firing weapon.
Beamer: A 'laser' beam/phaser type weapon.
Accelerator: A powerful kinetic weapon.
Lance/Lancer: A powerful beam/stream type weapon.
Arc (Gun): A sort of lightning generator.
Devastator: Fires big globs of energy (Plasma?).
Given it doesn't take place in the 'same' universe as modern earth (Although there is a bit of a story of humanity leaving the 'homeworld' several millennia ago, but its name has long been forgotten), some newer more ambiguous naming might work ok.