Quark-antiquark correlation in the pion
Abstract
The electromagnetic tensor for inclusive electron scattering off the pion Wμν for momentum transfers such that q+ = 0, ( q+ = q0 + q3) is shown to obey a sum-rule for the component W++. From this sum-rule, one can define the quark-antiquark correlation function in the pion, which characterizes the transverse distance distribution between the quark and antiquark in the light-front pion wave-function. Within the realistic models of the relativistic pion wave function (including instanton vacuum inspired wave function) it is shown that the value of the two-quark correlation radius ( r q overlineq) is near twice the pion electromagnetic radius ( rπ), where r π ≈ {2}/{3}fm. We also define the correlation length lcorr where the two-particle correlation have an extremum. The estimation of lcorr ≈ 0.3-0.5 fm is very close to estimations from instanton models of QCD vacuum. It is also shown that the above correlation is very sensitive to the pion light-front wave-function models.
- Publication:
-
Nuclear Physics A
- Pub Date:
- February 1997
- DOI:
- 10.1016/S0375-9474(97)00397-7
- arXiv:
- arXiv:hep-ph/9708278
- Bibcode:
- 1997NuPhA.623..456D
- Keywords:
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- High Energy Physics - Phenomenology;
- Nuclear Theory
- E-Print:
- 18 pages,include 3 Postscript figures (melo-2.ps,melo-3.ps and melo-4.ps), use latex,epsf,elsart, e-mail: pacheco@axpfep1.if.usp.br, tobias@fis.ita.cta.br, tomio@ift.unesp.br and dorokhov@thsun1.jinr.dubna.su, correction name authors. Accepted in Nucl.Phys. A (1997)