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arXiv · 2406.00818

Chiral Symmetry Breaking and Pion Decay in a Magnetic Field

Prabal Adhikari·Brian C. Tiburzi
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Abstract

The pattern of chiral symmetry breaking is exploited to compute vector and axial-vector pion matrix elements in a uniform magnetic field. Our results are model independent, and thereby constitute low-energy theorems that must be obeyed by QCD in external magnetic fields. Chiral perturbation theory, lattice QCD and Nambu-Jona-Lasinio results are compared. While there is some tension between chiral perturbation theory and lattice QCD, the tension between low-energy QCD and the Nambu-Jona-Lasinio model is more acute. As an application, the matrix elements are utilized to compute pion decay rates in a magnetic field.

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Prabal Adhikari, Brian C. Tiburzi. 2024-06-02. Chiral Symmetry Breaking and Pion Decay in a Magnetic Field. https://doi.org/10.1103/84zn-16sy

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