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Quark Index

A quark index is relevant because it is often more convenient to use a number instead of a letter to represent different kinds of quarks. So consider a seed noted by Z where

\mathsf{Z} \in \{ \mathsf{U, D, E, G, M, A, T, B, S, }  \mathsf{C,  \; } Ⓐ, Ⓑ, Ⓘ, Ⓦ, Ⓓ, Ⓛ }

The seed Z can be used to define an ordinary quark written as \mathsf{z} \equiv \{ \, \mathsf{Z}, \mathsf{O} \, \} and its associated anti-quark \overline{\mathsf{z}} \equiv \{ \, \mathsf{Z}, \overline{\mathsf{O}} \, \}. These quarks are occasionally referred to using \zeta, the Greek letter zeta, as shown in the table below. When used like this, zeta is called a quark index. The two particles  \mathsf{z} and  \overline{\mathsf{z}} are sometimes collectively called \zeta-type or Z-type quarks. This notation is especially helpful when using summation notation in formulae.

 \zeta\mathsf{Z}\mathsf{z}\overline {\mathsf{z}}
1U \mathsf{u}  \overline {\mathsf{u}}
2D \mathsf{d} \overline {\mathsf{d}}
3E \mathsf{e} \overline {\mathsf{e}}
4G \mathsf{g} \overline {\mathsf{g}}
5M \mathsf{m} \overline {\mathsf{m}}
6A \mathsf{a} \overline {\mathsf{a}}
7T \mathsf{t} \overline {\mathsf{t}}
8B \mathsf{b} \overline {\mathsf{b}}
9S \mathsf{s} \overline {\mathsf{s}}
10C \mathsf{c} \overline {\mathsf{c}}
11 \mathrm{a} \overline {\mathrm{a}}
12\mathrm{b}\overline {\mathrm{b}}
13 \mathrm{i} \overline {\mathrm{i}}
14 \mathrm{w} \overline {\mathrm{w}}
15\mathrm{d}\overline {\mathrm{d}}
16 \mathrm{l} \overline {\mathrm{l}}
The quark index notes a level of detailed analysis reminiscent of this Sumatran tampan.
Twenty Dragon Tampan (detail), Paminggir people. Lampung region of Sumatra 19th century, 65 x 81 cm. From the library of Darwin Sjamsudin, Jakarta. Photograph by D Dunlop.