The energy-dependent parts of baryon-baryon and baryon-antibaryon total cross sections at high energies are obtained from (i) factorization of the residues of the leading meson trajectories, and (ii) the connection between the absence of resonances in "exotic" channels and the flatness of meson-meson and meson-baryon total cross sections in these channels. (Such a connection leads to exchange degeneracies, all of which are consistent with experiment.) The following is proven: (a) Nucleon-nucleon (and certain other $B=2\mathrm{}$) total cross sections are flat whether or not trajectory couplings obey $\mathrm{SU}\left(3\right)\mathrm{}$; (b) the remaining $B=2\mathrm{}$ cross sections are flat if tensor and vector exchanges couple via $\mathrm{SU}\left(3\right)\mathrm{}$, with equal $\frac{F}{D}$ ratios at the baryon vertex; (c) non-Pomeranchuk contributions to baryon-antibaryon total cross sections persist in the 10, $\overline{1}\overline{0}$, and 27 channels despite the relaxation of assumptions regarding $B=2\mathrm{}$ systems. [Results similar to (a) and (b) have been assumed to hold in previous approaches.]

• Received 18 June 1969

DOI:https://doi.org/10.1103/PhysRev.188.2367