Quantum Chromo-Dynamics
And Nucleon Spin
Report by
F.Comm DL Wey
DCOSR: SFS – SFC
Among
the first subatomic particles to be discovered in the 20th century, they dwell within the nuclei of atoms [Thus, are given the term: Nucleons]. These objects make up more than 99.9% of the atomic structures of the matter in our everyday world [the remaining .1% is that of electrons].Of the most daunting of tasks for physicists, that of ‘Spin’ came about after a lengthy debate over the model for subatomic particles [which had been devised with but three species of quark in mind] began to show flaws.
Having been based upon the premise that there were only three species [later referred to as ‘flavors’] of quark, that of UP, DOWN, and STRANGE its flaws became evident with the discovery of the gluon, ‘antiquark’, muons [leptons], taus, kaons, and others.
Below are representations of the particles listed [beginning with the proton]:
1 2 3 4
1) At first observance, a proton appears as a blob, some 2x10-15 meters in diameter. Upon closer inspection
2) The quark model shows the proton to be a sum of the individual charges and spins.
3) Experiments revealed quarks to be likened to point particles within the proton [with the cords representing the ‘force’ holding them together].
4) The full complete picture of QCD is shown as a complicated, symphony of virtual quarks and anti-quarks [shown in red] and strange quarks [in purple]. Strange quarks are not usually associated with ordinary matter
The very structure of ‘spin’ is more influential in the subatomic realm than on the atoms themselves. In a hydrogen atom the alignment of the spins of both the proton and electron, increases the atoms ‘total’ spin but its mass is increased only slightly.
The difficulty lies in the fact that not all of the equations in QCD have solutions [as yet] especially where the nucleon is concerned. Experiments are being conducted on the subatomic scale to find the answers we seek. Further updates will be provided, as they become available.
