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arXiv · 2606.18507

$\pi^0$-$\gamma$ mixing in the presence of a strong magnetic field

D. Gomez Dumm·S. Noguera·N. N. Scoccola
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Abstract

We analyze the mixing between the $\pi^0$ meson and the photon in the presence of a strong uniform magnetic field, in the context of a two-flavor Nambu-Jona-Lasinio model. It is shown that only one specific photon polarization state can get mixed with the $\pi^0$ state, a fact that can be understood on general grounds. For magnetic fields with values up to 1 GeV$^2$/e, it is found that the effect of the mixing on the pion mass and pion-quark couplings is relatively small (below a level of 15%), which is at variance with previous results reported in the literature.

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D. Gomez Dumm, S. Noguera, N. N. Scoccola. 2026-06-16. $\pi^0$-$\gamma$ mixing in the presence of a strong magnetic field. https://arxiv.org/abs/2606.18507

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