Beta-tachyon
The beta-tachyon is a type of subatomic particle, an allotrope of the tachyon particle.

Beta-tachyons could be used to increase the strength of Federation starship shields by a factor of ten. The ship must remodulate its shields to emit a beta-tachyon pulse, and then project a series of antiproton beams into the shield bubble. ()

de:Tachyon
Particles