Comments on `Systematics of radial and angular-momentum Regge trajectories of light non-strange $q\bar{q}$ states', Masjuan, Arriola and Broniowski

Abstract

Masjuan, Arriola, and Broniowski [Phys. Rev. D85, 094006 (2012)] claim that the slope of the light-quark radial trajectories is 1.35 +- 0.04 GeV^2, disagreeing with the Crystal Barrel value 1.143 +- 0.013 GeV^2. There are defects in their choice of data. When these defects are revised, results come back close to the Crystal Barrel average for the slope. A revised average value is given here.

Comments: 12 pages, 1 figure, 1 Table. Comments simplified. References added to statistical and systematic errors of Crystal Barrel data. Further discussion of dispersive effects added with clarifications of wording. The conclusion is that the N_c = 3 world is different from N_c -> infinity