Up | Next | Prev | PrevTail | Tail |
This package calculates the color factor in non-abelian gauge field theories using an algorithm due to Cvitanovich.
Documentation for this package is in plain text.
Author: A. Kryukov.
Program "xCOLOR" is intended for calculation the colour factor in non-abelian gauge field theories. It is realized Cvitanovich algorithm [Cvi76]. In comparison to the program "COLOR" [KR88] many improvements were made. The package was written in symbolic mode. This version is more than \(10\) times faster than the one in [KR88].
After load the program by the following command load xcolor;
user can be able to use the next additional commands and operators.
Format: SUdim <any expression>;
Set the order of SU group.
The default value is 3, i.e. SU(3).
Format: SpTT <any expression>;
Set the normalization coefficient A: Sp(TiTj) = A*Delta(i,j). Default value is
1/2.
Format: QG(inQuark,outQuark,Gluon)
Describe the quark-gluon vertex. Parameters may be any identifiers. First and second of
then must be in- and out- quarks correspondently. Third one is a gluon.
Format: G3(Gluon1,Gluon2,Gluon3)
Describe the three-gluon vertex. Parameters may be any identifiers. The order of gluons
must be clock.
In terms of QG and G3 operators you input diagram in "color" space as a product of
these operators. For example.
Diagram: REDUCE expression: e1 ---->--- / \ | e2 | v1*..........*v2 <===> QG(e3,e1,e2)*QG(e1,e3,e2) | | \ e3 / ----<--- Here: --->--- quark ....... gluon
For more detail see [KR88].
Up | Next | Prev | PrevTail | Front |