{ "id": "0708.3526", "version": "v3", "published": "2007-08-27T02:20:50.000Z", "updated": "2007-11-17T06:34:04.000Z", "title": "1/N_c corrections to the magnetic susceptibility of the QCD vacuum", "authors": [ "Klaus Goeke", "Hyun-Chul Kim", "M. M. Musakhanov", "Marat Siddikov" ], "comment": "18 pages, 5 figures. Final version to appear in Phys. Rev. D", "journal": "Phys.Rev.D76:116007,2007", "doi": "10.1103/PhysRevD.76.116007", "categories": [ "hep-ph" ], "abstract": "We investigate the magnetic susceptibility of the QCD vacuum with the $1/N_c$ corrections taken into account, based on the instanton vacuum. Starting from the instanton liquid model we derive the gauged light-quark partition function in the presence of the current quark mass as well as of external Abelian vector and tensor fields. We consider the $1/N_c$ meson-loop corrections which are shown to contribute to the magnetic susceptibility by around 15% for the up (and down) quarks. We also take into account the tensor terms of the quark-quark interaction from the instanton vacuum as well as the finite-width effects, both of which are of order $\\mathcal{O}(1/N_c)$. The effects of the tensor terms and finite width turn out to be negligibly small. The final results for the up-quarks are given as: $\\chi< i\\psi^\\dagger \\psi>_0 \\simeq 35-40 \\mathrm{MeV}$ with the quark condensate $_0$. We also discuss the pion mass dependence of the magnetic susceptibility in order to give a qualitative guideline for the chiral extrapolation of lattice data.", "revisions": [ { "version": "v3", "updated": "2007-11-17T06:34:04.000Z" } ], "analyses": { "subjects": [ "11.15.Pg", "11.15.Kc", "11.10.Lm", "11.30.Rd" ], "keywords": [ "magnetic susceptibility", "qcd vacuum", "instanton vacuum", "tensor terms", "instanton liquid model" ], "tags": [ "journal article" ], "publication": { "publisher": "APS", "journal": "Physical Review D", "year": 2007, "month": "Dec", "volume": 76, "number": 11, "pages": 116007 }, "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable", "inspire": 759151, "adsabs": "2007PhRvD..76k6007G" } } }