We found it, the mother lode, the Flux Capacitor back from the Future

SLAC houses the longest linear accelerator in the world, making it “the world’s straightest object”. The main accelerator is buried 30 feet below ground passing underneath Highway 280, and colliding in this SLAC Large Detector (SLD), in the final focus area of the North and South beams.

The SLD was the main detector for the Stanford Linear Collider. It was designed primarily to detect Z bosons produced by the accelerator’s electron-positron collisions. The SLD operated from 1992 to 1998.