Quarkantiquark correlation in the pion
Abstract
The electromagnetic tensor for inclusive electron scattering off the pion W^{μν} for momentum transfers such that q^{+} = 0, ( q^{+} = q^{0} + q^{3}) is shown to obey a sumrule for the component W^{++}. From this sumrule, one can define the quarkantiquark correlation function in the pion, which characterizes the transverse distance distribution between the quark and antiquark in the lightfront pion wavefunction. Within the realistic models of the relativistic pion wave function (including instanton vacuum inspired wave function) it is shown that the value of the twoquark correlation radius ( r _{q overlineq}) is near twice the pion electromagnetic radius ( r_{π}), where r _{π} ≈ {2}/{3}fm. We also define the correlation length l_{corr} where the twoparticle correlation have an extremum. The estimation of l_{corr ≈ 0.30.5 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 lightfront wavefunction models.
 Publication:

Nuclear Physics A
 Pub Date:
 February 1997
 DOI:
 10.1016/S03759474(97)003977
 arXiv:
 arXiv:hepph/9708278
 Bibcode:
 1997NuPhA.623..456D
 Keywords:

 High Energy Physics  Phenomenology;
 Nuclear Theory
 EPrint:
 18 pages,include 3 Postscript figures (melo2.ps,melo3.ps and melo4.ps), use latex,epsf,elsart, email: 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)