Changes

Jump to navigation Jump to search
making progress
Line 20: Line 20:  
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:
 
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}
 
:<math>\begin{align}
−
n^0 &\to p^+ + e^- + \bar\nu_e \\
+
n^0 &\to p^+ + e^- + \bar\nu_e \qquad\textrm{neutron}\ \textrm{decay}\ \textrm{with}\ \textrm{electron}\ \textrm{emission}\\
−
p^+ &\to n^0 + e^+ + \nu_e \\
+
p^+ &\to n^0 + e^+ + \nu_e \qquad\textrm{proton}\ \textrm{decay}\ \textrm{with}\ \textrm{positron}\ \textrm{emission,}\ \textrm{not}\ \textrm{energetically}\ \textrm{possible}\ \textrm{in}\ \textrm{isolation}\\
−
n^0 + e^+ &\to p^+ + \bar\nu_e \\
+
n^0 + e^+ &\to p^+ + \bar\nu_e \qquad\qquad\textrm{positron}\ \textrm{capture,}\ \textrm{only}\ \textrm{happens}\ \textrm{if}\ \textrm{a}\ \textrm{positron}\ \textrm{happens}\ \textrm{to}\ \textrm{be}\ \textrm{nearby}\\
−
p^+ + e^- &\to n^0 + \nu_e
+
p^+ + e^- &\to n^0 + \nu_e \qquad\qquad\textrm{electron}\ \textrm{capture}
 
\end{align}</math>
 
\end{align}</math>
 +
The first of these is classical "beta decay", that is, the emission of a "beta ray", first discovered in the earliest days of radioactivity research.  The "beta rays" were soon identified as being just electrons.
 +
 +
The second is generally called "beta plus" decay, the positron being considered a "beta plus ray".  That, and the fourth one, electron capture, are beta transformations that occur for many isotopes.
 +
 +
Antiparticles.
 +
 +
Backwards.
    
Conservation laws (lepton number, baryon number, charge)
 
Conservation laws (lepton number, baryon number, charge)
SkipCaptcha, Automoderated users, edit
3,266

edits

Navigation menu