The near-threshold peak of the phi-photoproduction cross section and its interpretation

TL;DR

This paper investigates whether a resonance can explain the near-threshold peak in phi-photoproduction cross section, using a phenomenological approach to fit experimental data and explore implications for related processes.

Contribution

It introduces a specific J^P=3/2^- resonance model that fits the near-threshold phi-photoproduction data and explores its effects on omega photoproduction.

Findings

Resonance with mass ~2.08 GeV and width ~0.57 GeV fits the data well.

Helicity amplitude ratio differs in sign from known D13(2080).

Resonance improves omega photoproduction description with large OZI parameter.

Abstract

We study, within phenomenological Lagrangian approach, the possibility that the near-threshold peak found in the phi-photoproduction cross section is caused by a resonance. We show that, by employing a J^P=3/2^- resonance with a mass of 2.08 +/- 0.05 GeV and a width of 0.570 +/- 0.169 GeV, the LEPS data which include new data on nine spin-density matrix elements can indeed be described reasonably well. We also find that the ratio of helicity amplitudes A_1/2/A_3/2 calculated from the resulting coupling constants differs in sign from that of D13(2080). The resonance is further found to be able to improve the theoretical description of omega photoproduction against a new set of data if a large value for OZI evading parameter is assumed.