ϒ photoproduction on the proton at the Electron-Ion Collider

Oleksii Gryniuk,Marc Vanderhaeghen,Zein-Eddine Meziani,Sylvester Joosten

doi:10.1103/physrevd.102.014016

Oleksii Gryniuk, Marc Vanderhaeghen + Show 2 more

Open Access

https://doi.org/10.1103/physrevd.102.014016

Copy DOI

Abstract

We present a dispersive analysis with the aim to extract the $\Upsilon$-p scattering length from $\gamma p \to \Upsilon p$ experiments. In this framework, the imaginary part of the $\Upsilon$-p forward scattering amplitude is obtained from $\gamma p \to \Upsilon p$ cross section measurements, and is constrained at high energies from existing HERA and LHC data. Its real part is calculated through a once-subtracted dispersion relation, and the subtraction constant is proportional to the $\Upsilon$-p scattering length. We perform a feasibility study for $\Upsilon$ photo-production experiments at an Electron-Ion Collider and discuss the sensitivity and precision that can be reached in the extraction of the $\Upsilon$-p scattering length.

Highlights

The interaction between heavy quarkonia, such as J=ψ and Υ, and light hadrons or nuclei provides a unique window on the gluonic van der Waals interaction in quantum chromodynamics (QCD)
Being a small sized system, the heavy quarkonium QQcan be treated as a color dipole, and the effective two-gluon exchange interaction between the quarkonium and the light hadron or nucleus may be estimated from the knowledge of its chromoelectric polarizability; see Refs. [1,2,3] for reviews and references therein
The study of the excitation spectrum in the charmonium and bottomonium sectors above open charm and open bottom thresholds has revealed a plethora of new states, which cannot be explained as conventional QQbound states; see, e.g., [16] for a recent experimental review

Summary

Introduction

The interaction between heavy quarkonia, such as J=ψ and Υ, and light hadrons or nuclei provides a unique window on the gluonic van der Waals interaction in quantum chromodynamics (QCD). Being a small sized system, the heavy quarkonium QQcan be treated as a color dipole, and the effective two-gluon exchange interaction between the quarkonium and the light hadron or nucleus may be estimated from the knowledge of its chromoelectric polarizability; see Refs. [1,2,3] for reviews and references therein Provided this effective interaction is strong enough, a bound state between the QQstate and the light hadron or nucleus may be formed [4,5,6]. Several explanations for the nature of these exotic states have been put forward, ranging, among others, from

Objectives

Results

Conclusion