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The spectrum of states with one current acting on the adjoint vacuum of massless QCD2

A. Abrashkin·Y. Frishman·J. Sonnenschein
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Abstract

We consider a ``one current'' state, which is obtained by the application of a color current on the ``adjoint'' vacuum. This is done in $QCD_2$, with the underlying quarks in the fundamental representation. The quarks are taken to be massless, in which case the theory on the light-front can be ``currentized'', namely, formulated in terms of currents only. The adjoint vacuum is shown to be the application of a current derivative, at zero momentum, on the singlet vacuum. We apply the operator $M^2=2P^+P^-$ on these states and find that in general they are not eigenstates of $M^2$ apart from the large $N_f$ limit. Problems with infra-red regularizations are pointed out. We discuss the fermionic structure of these states.

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A. Abrashkin, Y. Frishman, J. Sonnenschein. 2004-11-10. The spectrum of states with one current acting on the adjoint vacuum of massless QCD2. https://doi.org/10.1016/j.nuclphysb.2004.10.019

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