ThePhysicsofRadiologychapter32new-放射物理-英文版-教学.ppt

The Fundamentals of Nuclear PhysicsPart twoBME College Sherman Sheen(辛辛学学刚刚)The Physics of RadiologyBeta Disintegration-emission n p+-+Z increases 1+emission p n+Z decreases 1 Occurred in the Nucleus-emission:lower right upper left +emission:upper left lower right the beta ray spectra for the decay of Cu-64 Beta Minus Decay total K.E.of and v is 1.71 MeV Beta Minus Decay mass of P-32 nucleus 31.973909 15 m0mass of S-32 nucleus 31.972073 16 m0 mass of-1 m0 mass of neutrino()0 total mass 31.972073 15 m0energy release 31.973909 15 m0 31.972073 15 m0(by subtraction)0.001836 amu0.001836 931.5=1.71 MeV Beta Plus Decay nuclear reactor:a neutron added to a stable nucleus high energy machines:a neutron removed from the parent nucleus Beta Plus Decay (total K.E.of+and is 1.20 MeV)positron+electron two photonsannihilation,1.022 MeV Electron Capture P+e(usually K electron)n+Internal ConversionAuger ElectronsSummary Beta DisintegrationBeta Minus DecayBeta Plus DecayElectron CaptureInternal ConversionAuger Electrons