Examples of beta decay in the following topics:
-
- Beta decay is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted from an atomic nucleus.
- Beta decay is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted from an atomic nucleus, as shown in .
- There are two types of beta decay.
- Beta decay is mediated by the weak force.
- The inset shows beta decay of a free neutron
-
- Gamma decay is a process of emission of gamma rays that accompanies other forms of radioactive decay, such as alpha and beta decay.
- Gamma decay accompanies other forms of decay, such as alpha and beta decay; gamma rays are produced after the other types of decay occur.
- For example, cobalt-60 decays to excited nickel-60 by beta decay through emission of an electron of 0.31 MeV.
- In certain cases, the excited nuclear state following the emission of a beta particle may be more stable than average; in these cases it is termed a metastable excited state if its decay is 100 to 1000 times longer than the average $10^{-12}$ seconds.
- Explain relationship between gamma decay and other forms of nuclear decay.
-
- Most odd-odd nuclei are highly unstable with respect to beta decay because the decay products are even-even and therefore more strongly bound, due to nuclear pairing effects.
- During this process, the radionuclide is said to undergo radioactive decay.
- Radioactive decay results in the emission of gamma rays and/or subatomic particles such as alpha or beta particles, as shown in .
- Alpha decay is one type of radioactive decay.
- Many other types of decay are possible.
-
- Through radioactive decay, nuclear fusion and nuclear fission, the number of nucleons (sum of protons and neutrons) is always held constant.
- Consider the three modes of decay.
- In gamma decay, an excited nucleus releases gamma rays, but its proton (Z) and neutron (A-Z) count remain the same:
- In beta decay, a nucleus releases energy and either an electron or a positron.
- Alpha decay is the only type of radioactive decay that results in an appreciable change in an atom's atomic mass.
-
- PET acquisition process occurs as the radioisotope undergoes positron emission decay (also known as positive beta decay), it emits a positron, an antiparticle of the electron with opposite charge.
-
- Gamma rays from radioactive decay are defined as gamma rays no matter what their energy, so that there is no lower limit to gamma energy derived from radioactive decay.
- Gamma decay commonly produces energies of a few hundred keV, and almost always less than 10 MeV.
- They are classically produced by the decay from high energy states of atomic nuclei, a process called gamma decay, but are also created by other processes.
- Exceptions to this convention occur in astronomy, where gamma decay is seen in the afterglow of certain supernovas, but other high energy processes known to involve other than radioactive decay are still classed as sources of gamma radiation.
- All ionizing radiation causes similar damage at a cellular level, but because rays of alpha particles and beta particles are relatively non-penetrating, external exposure to them causes only localized damage (e.g., radiation burns to the skin).
-
- Radioactive decay series describe the decay of different discrete radioactive decay products as a chained series of transformations.
- Radioactive decay series, or decay chains, describe the radioactive decay of different discrete radioactive decay products as a chained series of transformations.
- Most radioactive elements do not decay directly to a stable state; rather, they undergo a series of decays until eventually a stable isotope is reached.
- A parent isotope is one that undergoes decay to form a daughter isotope.
- While the decay of a single atom occurs spontaneously, the decay of an initial population of identical atoms over time, $t$, follows a decaying exponential distribution, $e^{-t}$, where $\lambda$ is called the decay constant.
-
- Alpha decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle that consists of two protons and two neutrons, as shown in .
- Alpha decay is the most common cluster decay because of the combined extremely high binding energy and relatively small mass of the helium-4 product nucleus (the alpha particle).
- Alpha decay typically occurs in the heaviest nuclides.
- Alpha decay is one type of radioactive decay.
- Many other types of decay are possible.
-
- $\displaystyle \beta \equiv \frac{\bf u}{c},~\text{so}~ \kappa = 1 - {\bf n} \cdot \beta$
- $\displaystyle {\bf E}(r,t) = \kern-2mm q \left [ \frac{({\bf n} - \beta)(1-\beta^2)}{\kappa^3 R^2} \right ]_\mathrm{ret}\!
- \frac{q}{c} \left [ \frac{\bf n}{\kappa^3 R} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ]_\mathrm{ret} \\ {\bf B}(r,t) = \kern-2mm\left [ {\bf n} \times {\bf E}(r,t) \right ]_\mathrm{ret}.$
- $\displaystyle {\bf E}_{rad}(r,t) = + \frac{q}{c} \left [ \frac{\bf n}{\kappa^3 R} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ] \\ {\bf B}_{rad}(r,t) = \left [ {\bf n} \times {\bf E}_{rad}(r,t) \right ].$
- $\displaystyle {\bf S} = {\bf n} \frac{q^2}{4\pi c \kappa^6 R^2} \left | {\bf n} \times \left \{ \left ( {\bf n} - \beta \right ) \times {\dot{\beta}} \right \} \right |^2$
-
- $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^3} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ]_\mathrm{ret} e^{i\omega t} d t.$
- $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^2} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ] e^{i\omega (t'+R(t')/c)} d t'.$
- $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^2} \times \left [ ({\bf n} - \beta) \times \dot{\beta} \right ]\right ] e^{i\omega (t'-{\bf n}\cdot {\bf r}(t')/c)} d t'.$
- $\displaystyle \frac{d W}{d\Omega d\omega} = \frac{q^2}{4\pi^2 c} \left | \int_{-\infty}^{\infty} \frac{{\bf n} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]}{\left ( 1-\beta\cdot {\bf n} \right )^2} e^{i\omega (t'-{\bf n}\cdot {\bf r}(t')/c)} d t' \right |.$
- $\displaystyle \frac{{\bf n} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]}{\left ( 1-\beta\cdot {\bf n} \right )^2} = \frac{d}{d t'} \left [ \frac{{\bf n} \times ({\bf n} \times \beta ) }{1-\beta\cdot {\bf n}} \right ].$