In
particle physics phenomenology
In physics, phenomenology is the application of theoretical physics to experimental data by making quantitative predictions based upon known theories. It is related to the philosophical notion of the same name in that these predictions describe ...
, chiral color is a
speculative model which extends
quantum chromodynamics (QCD), the generally accepted theory for the strong interactions of
quarks. QCD is a
gauge field theory
In physics, a gauge theory is a type of field theory in which the Lagrangian (and hence the dynamics of the system itself) does not change (is invariant) under local transformations according to certain smooth families of operations ( Lie group ...
based on a
gauge group
In physics, a gauge theory is a type of field theory in which the Lagrangian (and hence the dynamics of the system itself) does not change (is invariant) under local transformations according to certain smooth families of operations (Lie group ...
known as color SU(3)
C with an octet of colored
gluons acting as the force carriers between a triplet of colored quarks.
In Chiral Color, QCD is extended to a gauge group which is SU(3)
L × SU(3)
R and leads to a second octet of force carriers. SU(3)
C is identified with a
diagonal subgroup In the mathematical discipline of group theory, for a given group the diagonal subgroup of the ''n''-fold direct product is the subgroup
:\.
This subgroup is isomorphic to
Properties and applications
* If acts on a set the ''n''-fold diag ...
of these two factors. The gluons correspond to the unbroken gauge bosons and the color octet axigluons – which couple strongly to the quarks – are massive. Hence the name is Chiral Color. Although Chiral Color has presently no experimental support, it has the "aesthetic" advantage of rendering the Standard Model more similar in its treatment of the two short range forces, strong and weak interactions.
Unlike gluons, the axigluons are predicted to be massive. Extensive searches for axigluons at
CERN and
Fermilab
Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a United States Department of Energy national laboratory specializing in high-energy particle physics. Since 2007, Fermilab has been opera ...
have placed a lower bound on the axigluon mass of about .
Axigluons may be discovered when collisions are studied with higher energy at the
Large Hadron Collider.
References
Physics beyond the Standard Model
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