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On the Transition from Confinement to Screening in QCD_{1+1} Coupled to Adjoint Fermions at Finite N

F. Antonuccio·S. Pinsky
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Abstract

We consider SU(N) QCD_{1+1} coupled to massless adjoint Majorana fermions, where N is finite but arbitrary. We examine the spectrum for various values of N, paying particular attention to the formation of multi-particle states, which were recently identified by Gross, Hashimoto and Klebanov in the N -> infinity limit of the theory. It is believed that in the limit of vanishing fermion mass, there is a transition from confinement to screening in which string-like states made out of adjoint fermion bits dissociate into stable constituent ``single particles''. In this work, we provide numerical evidence that such a transition into stable constituent particles occurs not only at large N, but for any finite value of N. In addition, we discuss certain issues concerning the ``topological'' properties exhibited by the DLCQ spectrum.

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F. Antonuccio, S. Pinsky. 1998-05-27. On the Transition from Confinement to Screening in QCD_{1+1} Coupled to Adjoint Fermions at Finite N. https://doi.org/10.1016/s0370-2693(98)01023-5

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