Upper limits for the photoproduction cross section for the Phi--(1860) pentaquark state off the deuteron

TL;DR

This study searched for the Phi--(1860) pentaquark in photoproduction off deuteron targets but found no significant evidence, setting an upper limit on its production cross section.

Contribution

First search for Phi--(1860) pentaquark in photoproduction off deuteron with CLAS, establishing upper limits on its cross section.

Findings

No significant signal observed near 1.860 GeV

Set a 90% confidence level upper limit of 0.7 nb on cross section

Photoproduction cross section constrained in 4.5-5.5 GeV photon energy range

Abstract

We searched for the Phi--(1860) pentaquark in the photoproduction process off the deuteron in the Xi- pi- decay channel using CLAS. The invariant mass spectrum of the Xi- pi- system does not indicate any statistically significant enhancement near the reported mass M = 1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90% confidence level upper limit of 0.7 nb for the photoproduction cross section of Phi--(1860) with a consecutive decay into Xi- pi- in the photon energy range 4.5 GeV < Egamma < 5.5 GeV.