${\rm Y}$ photo-production on the proton at the Electron-Ion Collider

Abstract

We present a dispersive analysis with the aim to extract the ${\rm Y}$-p scattering length from $\gamma p\to {\rm Y}p$ experiments. In this framework, the imaginary part of the ${\rm Y}$-p forward scattering amplitude is obtained from $\gamma p\to {\rm Y}p$ 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 ${\rm Y}$-p scattering length. We perform a feasibility study for ${\rm Y}$ photo-production experiments at an Electron-Ion Collider and discuss the sensitivity and precision that can be reached in the extraction of the ${\rm Y}$-p scattering length.