Graser
From Cosmic Fate
A "Graser" (or gamma ray frequency laser) is gamma ray weapon that uses nuclear explosions to produce a massive burst of gamma radiation, which is than concentrated via mirrors to form a semi-coherent beam of devastating power. The Origins of this technology actually date back to 20th century earth. The technology became practical in 2093, however the chaos of the 2100's lead to Graser technology among many other things becoming nearly lost. Despite such by 2270 both the United Republic of Earth & Commonwealth of Mars have made great strides in developing Graser technology though with very different directions.