Kaonic deuterium and low-energy antikaon-nucleon interaction

TL;DR

This paper presents a precise three-body calculation of kaonic deuterium's energy shift and width, utilizing realistic antikaon-nucleon interactions constrained by experimental data, providing improved understanding of low-energy antikaon-nucleon interactions.

Contribution

It introduces an accurate three-body calculation method for kaonic deuterium, incorporating realistic interactions constrained by recent experimental data.

Findings

Energy shift of approximately 0.67 keV

Width of approximately 1.02 keV

Uncertainties estimated at 10%

Abstract

A new evaluation of the $1s$ level shift and width of kaonic deuterium is presented based on an accurate $\bar{K}NN$ three-body calculation, using as input a realistic antikaon-nucleon interaction constrained by the SIDDHARTA kaonic hydrogen data. The three-body Schr\"odinger equation is solved with a superposition of a large number of correlated Gaussian basis functions extending over distance scales up to several hundred fm. The resulting energy shift and width of the kaonic deuterium $1s$ level are $E\simeq 0.67$ keV and $\Gamma\simeq 1.02$ keV, with estimated uncertainties at the 10% level.