Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab

TL;DR

This paper reports precise measurements of differential cross sections and recoil polarization for the gamma p to K+ Lambda reaction over a broad energy range, enhancing understanding of photoproduction mechanisms.

Contribution

It provides new, high-precision data covering higher energies and wider angles, improving upon previous measurements and enabling detailed analysis of non-resonant processes.

Findings

Measurements agree with previous results, confirming existing data.

Enhanced energy coverage allows for better study of production mechanisms.

Data precision and range are significantly improved.

Abstract

We present measurements of the differential cross section and Lambda recoil polarization for the gamma p to K+ Lambda reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ p pi- and K+ p (missing pi -) final-state topologies; results from these analyses were found to exhibit good agreement. These differential cross section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300 MeV increase in energy coverage. The recoil polarization data agree well with previous results and offer a large increase in precision and a 500 MeV extension in energy range. The increased center-of-mass energy range that these data represent will allow for independent study of non-resonant K+ Lambda photoproduction mechanisms at all production angles.