Journal article

Publication year: 2005

Pages: 425-447

Journal: Nuclear Physics A: Nuclear and Hadronic Physics

Volume number: 747

Issue number: 2-4

ISSN: 0375-9474

eISSN: 1873-1554

Open access status: Green

DOI Link: https://doi.org/10.1016/j.nuclphysa.2004.10.011

Publisher: Elsevier

Abstract: 
QCD sum rules are studied for the vector-isovector current at finite baryon density in the limit of large number of colors N-C. For the condensate side it is shown that in this limit the four-quark condensate factorizes also for the finite density case. At the hadronic side the medium dependence is expressed in terms of the current-nucleon forward scattering amplitude. Generalizing vector meson dominance we allow for a direct coupling of the current to the nucleon as well as a coupling via the rho meson. We discuss the N-C dependence of (a) modifications of the pion cloud of the rho meson, (b) mixing with other mesons (in particular a(1) and omega) and (c) resonance-hole excitations R N-1. We show that only the last effect survives in the large-N-C limit. Saturating the sum rules with a simple hadronic ansatz which allows for the excitation of the D-13(1520) we determine the coupling of the latter to the rho-nucleon and the photon-nucleon system. These couplings are hard to determine from vacuum physics alone. (C) 2004 Elsevier B.V. All rights reserved.

Harvard Citation style: Leupold, S. and Post, M. (2005) QCD sum rules at finite density in the large-N_c limit:: the coupling of the p-nucleon system to the D₁₃(1520), Nuclear Physics A: Nuclear and Hadronic Physics, 747(2-4), pp. 425-447. https://doi.org/10.1016/j.nuclphysa.2004.10.011

APA Citation style: Leupold, S., & Post, M. (2005). QCD sum rules at finite density in the large-N_c limit:: the coupling of the p-nucleon system to the D₁₃(1520). Nuclear Physics A: Nuclear and Hadronic Physics. 747(2-4), 425-447. https://doi.org/10.1016/j.nuclphysa.2004.10.011