Strangeness suppression of qq creation observed in exclusive reactions

Phys Rev Lett. 2014 Oct 10;113(15):152004. doi: 10.1103/PhysRevLett.113.152004. Epub 2014 Oct 10.

Abstract

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK(+), pπ(0), and nπ(+), with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq creation probabilities for the first time in exclusive two-body production, in which only a single qq pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.