QCD sum rules for magnetically induced mixing between $\eta_c$ and $J/\psi$

TL;DR

This paper uses QCD sum rules to analyze how strong magnetic fields induce mixing between $ ext{η}_c$ and $J/ψ$ charmonia, revealing that mixing effects dominate their mass shifts.

Contribution

It introduces a field-theoretical implementation of mixing effects in QCD sum rules for charmonia under magnetic fields, highlighting their dominant role.

Findings

Mixing effects significantly alter charmonia masses in magnetic fields.

Sum rules are saturated by mixing effects with phenomenological parameters.

Mass shifts are primarily due to $ ext{η}_c$-$J/ψ$ mixing in strong magnetic fields.

Abstract

We investigate the properties of charmonia in strong magnetic fields by using QCD sum rules. We show how to implement the mixing effects between $\eta_c$ and $J/\psi$ on the basis of field-theoretical approaches, and then show that the sum rules are saturated by the mixing effects with phenomenologically determined parameters. Consequently, we find that the mixing effects are the dominant contribution to the mass shifts of the charmonia in strong magnetic fields.