Precise dispersive data analysis of the f0(600) pole

TL;DR

This paper uses recent precise experimental data and advanced dispersion relation techniques to accurately determine the sigma resonance pole position, improving the precision of dispersive data analysis in particle physics.

Contribution

It introduces a modified set of Roy-like equations with one subtraction, enhancing the precision of sigma resonance pole determination from experimental data.

Findings

Precise sigma pole position determined using FDR and Roy's equations.

Modified Roy-like equations with one subtraction improve precision.

Matching parametrizations at different energies has negligible effect on results.

Abstract

We review how the use of recent precise data on kaon decays together with forward dispersion relations (FDR) and Roy's equations allow us to determine the sigma resonance pole position very precisely, by using only experimental input. In addition, we present preliminary results for a modified set of Roy-like equations with only one subtraction, that show a remarkable improvement in the precision around the sigma region. We also improve the matching between the parametrizations at low and intermediate energy of the S0 wave, and show that the effect of this on the sigma pole position is negligible.