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Дата индексирования: Mon Oct 1 22:46:06 2012
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Tensor ghost.

Whereas the Faddeev-Popov and Goldstone ghosts are standard elements of modern quantum field theory, the tensor ghost is an original CompHEP  invention. This is an auxiliary field with a point-like propagator which is used to construct vertices with complicated color structure, for example, the four-gluon vertex.

The tensor ghost is generated automatically for any vector particle with a non-trivial SU(3) color group representation. Its name is constructed by means of suffix 't'. This ghost is commutative, and satisfies the same conjugation rule as the prototype particles. It is Lorentz-transformed like a tensor field. The propagator is

$$<0\vert T[\mbox{A+.t}^{m_1M_1}(p_1), \; A.t^{m_2M_2}(p_2)]\v... ...{(2 \pi)^4i} \; \delta(p_1+p_2) \, g^{m_1m_2}\, g^{M_1M_2}\;.$$ (7)