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Unified gauge model; SU_colour (3)⊗SU_L (2)⊗ U (1); spin-one colour gluons; integrally-charged quarks; deep inelastic lepton-hadron scattering; parton model; Bjorken scaling; electron-positron annihilation

Deep inelastic weak and electromagnetic processes are considered within the parton framework taking the partons to be integrally charged quarks and coloured gluons. Despite the participation of the spin-one gluons in these processes, scaling is shown to be maintained by treating the problem in a unified gauge model based on the groupSU (3)_colour⊗SU_L (2)⊗U(1). This is a consequence of the vector-dominance type of couplings between the gluons and the weak or electromagnetic vector bosons which are induced by the spontaneous breakdown of gauge symmetry. As a further consequence it is found that in the asymptotic region far above the gluon masses the colour octet parts of the weak and electromagnetic currents of the quarks are damped so that, in particular, the integrally charged quarks behave as fractionally charged quarks in this region.

G Rajasekaran¹ Probir Roy¹

1. Tata Institute of Fundamental Research, Bombay - 400005

Published

December 1975

Manuscript received

6 October 1975