Nuclear particle classification is required because experimental physicists have observed several hundred short-lived material particles that are smaller than atoms, but bigger than quarks. These little bits of matter were discussed earlier. Sometimes they are called sub-atomic particles. For EthnoPhysics, the most important scientific reference for information about nuclear particles is provided by the Particle Data Group . This organization is an international collaboration of particle physicists that compile and reanalyze published results. Their excellent work produces a voluminous reference of more than a thousand pages. The classification of nuclear particles is required to organize this rich legacy of precise, reproducible experimental data. So next we sort out nuclear particles by considering their quark content.
Particles are described by their quark coefficients which are noted by , and . Nuclear particles are identified by their quantum numbers and characterized as either mesons, baryons, or perhaps leptons. Many important particle attributes are defined from rather than , so complicated models that include quarks that are paired with their anti-quarks may be constructed. Because of this possibility, classification depends on assessing the minimum number of quarks that are at the heart of each categorical family.
Here is a simple plan based on a tally of the baryonic and rotating seeds in a particle’s core. It just requires counting up, down, top and strange quarks, and nothing more. Lower bounds for Z-type quarks are noted by . These minima are used to sort nuclear particles into 25 different family groups, so they are called familial seeds. Specific particles, and their excited states, are then modeled by adding more quarks to the familial patterns
Down Quarks are Key to Nuclear Particle Classification
The most important characteristic for nuclear particle classification is the minimum number of down quarks in their core. The list below shows in descending order as particles become less baryonic and more leptonic, finally arriving at the Higgs boson.
Click on any icon or label in the following list for a more detailed look at the quark models for each family.
Click on any icon or label in the foregoing list for a more detailed look at the quark models for each family. Next we consider compound quarks that are bigger and heavier: Newtonian Particles.