Scaling and Resonances in Elementary K^+ Lambda Photoproduction
Abstract
Recent cross section data for the reaction gamma + p \to K^+ + Lambda are examined for evidence of scaling in both the low-t Regge domain and in the high \sqrt{s} and -t domain where constituent counting may apply. It is shown that the reaction does scale in both regimes. At large center of mass angles, s^{-7} scaling appears to hold at essentially all -t, but with angle-dependent oscillations. The scaled data show particularly strong evidence for s-channel resonances for -t below 2 GeV^2 and for W below about 2.3 GeV. The dominant contributions are consistent with an N^* S_{11} resonance at 1690 MeV, a P_{13} at 1920 MeV, and a D_{13} resonance at 2100 MeV, which interfere to give the observed strong angular dependence.
Cite
@article{arxiv.1012.2126,
title = {Scaling and Resonances in Elementary K^+ Lambda Photoproduction},
author = {Reinhard A. Schumacher and Misak M. Sargsian},
journal= {arXiv preprint arXiv:1012.2126},
year = {2011}
}
Comments
Accepted by Physical Review C, 11 Pages, 8 Figures; fixed figure and reference formats per PRC