Project SEMELE

Semele was an unfinished (though reportedly failed) plasma rifle project, developed by Poseidon Energy.

Background
The technology used in Semele, specifically the Heisenberg compensation field when dealing with matter conversion, was later used to develop RobCo Industries' own model of the plasma rifle, which proved to be successful enough for deployment in the Enclave Armed Forces.

Appearances
Semele is only mentioned in Fallout: New Vegas.

Behind the scenes
In Greek mythology, Semele (Σεμέλη) was the mortal mother of Dionysus, according to one story of the latter's origin.