Answer: muon

AnswerCrossword Clue
MUONElementary particle
muonlepton similar in most respects to the electron except that it is unstable, it may be positively charged, and its mass is approximately 207 times greater; the positively charged muon is the antiparticle of the negatively charged muon
MUONShort-lived atomic particle
MUONParticle of cosmic radiation
MUONSubatomic bit
MUONShort-lived, charged lepton
MUONSubatomic particle more massive than an electron
MUONParticle created by a cosmic ray
MUONUnstable lepton
MUONShort-lived particle
MUONPhysics particle
MUONCharged lepton
MUONType of unstable particle
MUONAtomic particle
MUONSubatomic particle
MUONParticle that can temporarily replace an electron
MUONUnstable subatomic particle
MUONUnstable particle