4th Week: Decays, Tunneling and Cross Sections
Nuclear Radiation
When looking at the table of nuclides it is obvious that the valley of stability is only a small percentage of all known nuclei. So most nuclei are considered unstable. To become stable these nuclides emit ionizing particles and radiation, resulting in a loss of energy from the original nuclei. This Process is called radioactive decay.
Alpha Decay
Alpha decay, which is usually seen in heavier elements, is the transformation of a parent nucleus to a daughter nucleus through the emission of a helium nucleus.
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _{Z}^{A}\textrm{X}\to \; _{Z-2}^{A-4}\textrm{Y} + \;_{2}^{4}\textrm{He}}
Beta Decay
There are three types of Beta decays, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \beta^-} -decay, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \beta^+} -decay, and electron capture.
The first one, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \beta^-} decay, occurs when a nucleus with an over abundance of neutrons transforms to a more stable nucleus by emitting an electron. This process can be denoted as:
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _{Z}^{A}\textrm{X}\to \; _{Z+1}^{A}\textrm{Y} + \;e^-}
From electric-charge conservation, the proton number in such decays is increased by one unit.
Likewise, a Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \beta^+} -decay occurs when a proton-rich nucleus emits a positron, therefore reducing the nuclear charge by one.
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle _{Z}^{A}\textrm{X}\to \; _{Z-1}^{A}\textrm{Y} + \;e^+}
Gamma Decay
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle E_{\alpha } = E_{center of mass} \frac{M_{product}+M_{reaction}}{M_{reaction}}, \; \; \; \; E_{center of mass} = E_{\alpha} \frac{M_{reaction}}{M_{reaction}+M_{product}}}