Regge trajectories with nonplanar cylinder corrections in broken SU(4)

Abstract

In the framework of the topological expansion, the analysis of Chew and Rosenzweig indicates a shift in the first-level (planar) $I=0$ poles. This analysis has been extended to broken SU(4) by including a charmed trajectory, thus allowing for the renormalization effects due to the charm-production threshold. The trajectory shapes and their quark contents are considered for the ${J}^{P}={1}^{\ensuremath{-}}$ and ${2}^{+}$ mesons as functions of ${\ensuremath{\alpha}}_{4}(0)$ and $t$. It is shown that a high-lying charm trajectory can lead to a renormalization of the $f$-meson trajectory to an intercept above unity, and thus to a value approaching the bare Pomeron of the Gribov calculus. Finally, the physical implications of our results are discussed.