A second look at string-inspired models for proton-proton scattering via Pomeron exchange

Abstract

Abstract We re-examine a string dual model for elastic proton-proton scattering via Pomeron exchange. We argue that the method of “Reggeizing” a propagator to take into account an entire trajectory of exchanged particles can be generalized, in particular by modifying the value of a mass-shell parameter in the model. We then fit the generalized model to scattering data at large s and small t. The fitting results are inconclusive, but suggest that a better fit might be obtained by allowing the mass-shell parameter to vary. The model fits the data equally well (roughly) for a wide range of values of the mass-shell parameter, but the other fitting parameters (the slope and intercept of the Regge trajectory, and the coupling constant and dipole mass from the proton-proton-glueball coupling) are then inconsistent with what we expect. On the other hand, using the traditional method of Reggeization generates a weaker fit, but the other parameters obtain more physically reasonable values. In analyzing the fitting results, we also found that our model is more consistent with the s=1800 $$ \sqrt{s}=1800 $$ GeV data coming from the E710 experiment than that coming from the CDF experiment, and that our model has the greatest discrepancy with the data in the range 0.5 GeV2 < |t| < 0.6 GeV2, suggesting that the transition from soft Pomeron to hard Pomeron may occur closer to t = −0.5 GeV2 rather than t = −0.6 GeV2 as previously thought.

Keywords

• Gauge-gravity correspondence
• AdS-CFT Correspondence