RT Book, Section A1 Cooke, C. David A1 Galt, James R. A1 Tauxe, E. Lindsey A2 Heller, Gary V. A2 Hendel, Robert C. SR Print(0) ID 1190155546 T1 Fundamentals of Nuclear Cardiology Physics T2 Nuclear Cardiology: Practical Applications, 4e YR 2022 FD 2022 PB McGraw Hill LLC PP New York, NY SN 9781264257201 LK accesscardiology.mhmedical.com/content.aspx?aid=1190155546 RD 2024/10/14 AB KEY POINTSElements are defined by the number of protons in the nucleus. Nuclides are defined by the number of protons and the number of neutrons.The ratio of protons to neutrons determines the stability of a nucleus.Unstable nuclei decay to a more stable state through several different mechanisms: α decay, β− decay, β+ (positron) decay, electron capture, and isomeric transition.The rate at which unstable nuclei decay can be described by the decay constant. It is often more convenient to describe the rate of decay by the half-life.The interaction of radiation with matter is dependent on the energy and type of the radiation, as well as the atomic number (Z number) of the matter.Attenuation is the loss of radiation as it passes through matter and is absorbed or deflected.