Determination of the total width of the eta-prime meson

TL;DR

This study precisely measures the total width of the eta-prime meson using proton-proton collisions at COSY, achieving the most accurate result to date through advanced detection and analysis techniques.

Contribution

It provides the most precise measurement of the eta-prime meson's total width, utilizing a novel experimental setup and data analysis at multiple beam momenta.

Findings

Total width of eta-prime meson is 0.226±0.017(stat)±0.014(syst.) MeV.

Achieved a mass resolution of 0.33 MeV/c^2.

Used over 2300 reconstructed events for high precision.

Abstract

The aim of this work was to determine the total width of the eta-prime meson. The investigated meson was produced via the pp->ppeta-prime reaction in the collisions of beam protons from COSY synchrotron with protons from a hydrogen cluster target. The COSY-11 detector was used for the measurement of the four-momentum vectors of outgoing protons. The mass of unregistered meson was determined via the missing mass technique, while the total width was directly derived from the mass distributions established at five different beam momenta. Parallel monitoring of the crucial parameters (e.g. size and position of the target stream) and the measurement close-to-threshold permitted to obtain mass resolution of FWHM = 0.33 MeV/c^2. Based on the sample of more than 2300 reconstructed pp->ppeta-prime events the determined total width of the eta-prime meson amounts to 0.226+-0.017(stat.)+-0.014(syst.) MeV, which is the most precise measurement until now.