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In particle physics, the quark model is a classification scheme for hadrons in terms of their valence quarks—the quarks and antiquarks that give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)" , or the Eightfold Way , the successful classification scheme organizing the large number of lighter hadrons that ...
In physics, the eightfold way is an organizational scheme for a class of subatomic particles known as hadrons that led to the development of the quark model. Both the American physicist Murray Gell-Mann and the Israeli physicist Yuval Ne'eman independently and simultaneously proposed the idea in 1961.
Since only the u and d mass are similar, this description of particle mass and charge in terms of isospin and flavour quantum numbers works well only for octet and decuplet made of one u, one d, and one other quark, and breaks down for the other octets and decuplets (for example, ucb octet and decuplet).
These lists detail all known and predicted baryons in total angular momentum J = 1 / 2 and J = 3 / 2 configurations with positive parity. [5]Baryons composed of one type of quark (uuu, ddd, ...) can exist in J = 3 / 2 configuration, but J = 1 / 2 is forbidden by the Pauli exclusion principle.
A combination of three u, d or s-quarks with a total spin of 3/2 form the so-called baryon decuplet. The lower six are hyperons. Being baryons, all hyperons are fermions. That is, they have half-integer spin and obey Fermi–Dirac statistics. Hyperons all interact via the strong nuclear force, making them types of hadron.
The discovery was announced on 12 June 2007. It was the first known particle made of quarks from all three quark generations – namely, a down quark, a strange quark, and a bottom quark. The DØ and CDF collaborations reported the consistent masses of the new state. The Particle Data Group world average mass is 5.7924 ± 0.0030 GeV/c 2.
en: This shows the first baryon decuplet grouped according to the SU(3) scheme (« Eightfold way »). On this figure, in the standard layout : I 3 is the isospin component axis. Q is the electric charge axis. S is the strangeness axis. The main quark content is indicated within the pink circles.
For a strange quark, with electric charge − + 1 / 3 , a baryon number of + + 1 / 3 , and strangeness −1, we get a hypercharge Y = − + 2 / 3 , so we deduce that I 3 = 0 . That means that a strange quark makes an isospin singlet of its own (the same happens with charm , bottom and top quarks), while up and down constitute ...