The πNN and πNN(1535) couplings in QCD
نویسنده
چکیده
We study the two point correlation function of two nucleon currents sandwiched between the vacuum and the pion state. The light cone QCD sum rules are derived for the πNN coupling gπNN and the πNN(1535) coupling gπNN∗ . The contribution from the excited states and the continuum is subtracted cleanly through the double Borel transform with respect to the two external momenta, p1, p 2 2 = (p − q). We first improve the original sum rule for gπNN and determine the value of the pion wave function φπ(u0 = 1 2 ) = 1.5± 0.2, which is a fundamental nonperturbative quantity like the quark condensate. Our calculation shows that the πNN(1535) coupling is strongly suppressed. PACS Indices: 13.75.Gx; 14.20.Gk; 14.40.Aq; 13.75.Cs; 12.38.Lg
منابع مشابه
The suppression of πNN(1535) coupling in QCD
The light cone QCD sum rules are employed to calculate the πNN(1535) coupling gπNN∗ . We study the two point correlation function of two nucleon currents sandwiched between the vacuum and the pion state. The contribution from the excited states and the continuum is subtracted cleanly through the double Borel transform with respect to the nucleon andN(1535) momenta, p1, p 2 2 = (p−q) . Our calcu...
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تاریخ انتشار 1998