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Beta decay involves the "weak force", unlike alpha decay, which involves the "strong force". Nevertheless, beta decay has some extremely far-reaching consequences for [[radioactivity]], nucleosynthesis, and supernovas.
Beta decay involves the "weak force", unlike alpha decay, which involves the "strong force". Nevertheless, beta decay has some extremely far-reaching consequences for [[radioactivity]], nucleosynthesis, and supernovas.
The weak force is one of the four fundamental forces currently believed to exist:
*the gravitational force
*the electromagnetic force
*the weak force
*the strong force
The electric and magnetic forces were once considered to be separate, but they were unified so straightforwardly in the late 19<sup>th</sup> century that they are no longer treated as separate. The electromagnetic and weak forces were unified in the late 1960's, into the "electroweak force", but that connection is sufficiently esoteric that it has not supplanted the separate electromagnetic and weak forces. There are "grand unified theories" unifying the last three of these forces, and the physics community continues to search for a "theory of everything" that brings gravity into the picture. For all practical purposes, the four forces listed above are generally considered the fundamental forces.
The first two of these forces are well known without specialized knowledge of nuclear physics, mostly because they operate at macroscopic distances. The last two only operate at microscopic distances (about 10<sup>-15</sup> meters, or the diameter of a proton), so they are limited to subatomic particles.
*Q: Why are they called "forces"? What is doing the pushing?
*A: The term "force", applied to the gravitational and electromagnetic forces, is obviously reasonable. Also, the strong force could sort of be thought of as a force, making nucleons stick together. It takes a certain amount of mechanical pressure to pull nucleons out of a nucleus. But the weak "force" is hard to visualize as a force. Nevertheless, all four of these interactions are called "forces" for historical consistency.
The weak force acts on just abut every particle that exists—baryons (protons and neutrons), hadrons (various other things made of quarks), leptons (electrons, neutrinos, etc.), bosons, and so on. For example, the interaction shown in the above right corner shows weak interactions involving up and down quarks, a "weak vector boson", an electron, and an antineutrino. For all but extremely esoteric analysis of fundamental particle physics, hardly any of that matters. What's important is that a neutron turned into ("decayed into") a proton, and electron and an antineutrino. The various quarks, and the vector boson underwent beta transformations, but, in a simpler sense, we can just say that the neutron underwent a beta transformation. The interaction shown in the figure is the first of these:
:<math>\begin{align}
n^0 &\to p^+ + e^- + \bar\nu_e \\
p^+ &\to n^0 + e^+ + \nu_e \\
n^0 + e^+ &\to p^+ + \bar\nu_e \\
p^+ + e^- &\to n^0 + \nu_e
\end{align}</math>
Conservation laws (lepton number, baryon number, charge)
Anything possible if energy is released.
==References==
==References==