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The pion form factor within the hidden local symmetry model

  • M. Benayoun
  • P. David
  • L. DelBuono
  • Ph Leruste
  • H. B. O'Connell
Original Paper

Abstract.

We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. This implies an s-dependent dressing of the \(\rho-\gamma\) VMD coupling and an account of several coupled channels. The corresponding function \(F_\pi(s)\) provides nice fits of the pion form factor data from s=-0.25 to s=1 GeV2. It is shown that the coupling to \(K \overline{K}\) has little effect, while \(\omega \pi^0\) improves significantly the fit probability below the \(\phi\) mass. No need for additional states like \(\rho(1450)\) shows up in this invariant-mass range. All parameters, except for the subtraction polynomial coefficients, are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of \(F_\pi(s)\) at s=0 up to \({\cal O} (s^2)\) and with the phase shift data on \(\delta_1^1(s)\) from threshold to somewhat above the \(\phi\) mass. The \(\omega\) sector is also examined in relation with recent data from CMD-2.

Keywords

Phase Shift Form Factor Additional State Local Symmetry Analyticity Requirement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin/Heidelberg 2003

Authors and Affiliations

  • M. Benayoun
    • 1
    • 2
  • P. David
    • 2
  • L. DelBuono
    • 2
  • Ph Leruste
    • 2
  • H. B. O'Connell
    • 3
  1. 1.Laboratoire Européen pour la Recherche NucléaireCERNGenève 23Switzerland
  2. 2.Laboratoire Européen pour la Recherche NucléaireLPNHE des Universités Paris VI et VII-IN2P3ParisFrance
  3. 3.Laboratoire Européen pour la Recherche NucléaireFermilabBataviaUSA

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