electron e KEGG:C05359 0.000548579903 beta -1 PMID:21614077 electron Elektron e(-) Wikipedia:Electron beta-particle chebi_ontology Elementary particle not affected by the strong force having a spin 1/2, a negative elementary charge and a rest mass of 0.000548579903(13) u, or 0.51099906(15) MeV. CHEBI:10545 negatron beta(-) 0.0 e- lepton