Ghose-Eliminating Mechanism and Trajectory Parameter ofA2by Photoproduction Sum Rule

Abstract

The $A_2$ trajectory and residue functions are obtained and are found to change sign around $t=-0.5\mathrm{}$ Ge${\mathrm{V}}^2$. This strongly suggests the Chew or the no-compensation mechanism of ghost elimination. The trajectory parameter $\alpha \mathrm{}\left(t\right)\mathrm{}$ also agrees well with existing estimates.