Chapter 2. Radiation 1. Radioactivity 2. Radiation interaction with matter 3. Radiation doses and hazard assessment
Chapter 2. Radiation 1.Radioactivity 2.Radiation interaction with Matter 3.Radiation Doses and hazard Assessment
2. 1 Radioactivit 1)Overview 2) Types of radioactive decay 3) Energetics of Radioactive Decay 4)Characteristics of Radioactive Decay 5)Decay Dynamics 6) Naturally occurring Radionuclides
1) Overview 2) Types of Radioactive Decay 3) Energetics of Radioactive Decay 4) Characteristics of Radioactive Decay 5) Decay Dynamics 6) Naturally Occurring Radionuclides 2.1 Radioactivity
c)Beta Decay Spectra and Neutrino A Beta Decay Scheme A Typical Beta Spectrum β ity #of阝 E β- decay:2P→[z+D]++-e+v Pauli: Neutrino with spin 1 2 is emitted simultaneously with beta, carrying the missing energy
3 c) Beta Decay Spectra and Neutrino Pauli: Neutrino with spin 1 /2 is emitted simultaneously with beta, carrying the missing energy. A Typical Beta Spectrum Intensity or # of Energy of E max A Beta Decay Scheme P Z → DZ+1 + – + v ?
c B-decay: Ap -[z+AD]*+-ie+v QB-/c2=M(EP)-[M(z+4D1*)+mB-+my M(2p)-[(M(Z+D)-me]+mB-+mi M(aP)-M(+AD) The mass of the neutrino is negligibly small eB-/c2=M(2P)-M(z+1D)-E /c2 Cl(3724m) B max B 1(319% -3810 kev 2(105%)7619%) 2167 65(576%)Y(424%) 、=4917 Ar(stable)
c) The mass of the neutrino is negligibly small
d)Positron Decay Energy B+ decay: 2P=_1D]++ie+v Positron emission Rp+/c2=M(2P)-[M(2-AD12)+m(+ie)+my M(2P)-IOM(Z-AD)+me)+mg++my M(P)-M(Z-AD)-2me oQ Qe+/c2=M(2P)-M(z-1D)-2me-E'/c2 B)max Q B
5 d) Positron Decay Energy Positron Emission + –