Low-energy sum rules and large-Nc consistency conditions

  title={Low-energy sum rules and large-Nc consistency conditions},
  author={Wojciech Broniowski},
  journal={Nuclear Physics},
Abstract The large- N c consistency conditions for axial-vector and isovector magnetic couplings of pions to baryons are discussed from the point of view of low-energy current-algebra sum rules (Adler-Weisberger, Cabibbo-Radicati). In particular, we show how the result that ratios of axial-vector and isovector magnetic coupling constants get corrections only at the order 1/ N c 2 follows from the N c -counting of appropriate cross sections. This counting is performed using various approaches at… Expand
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