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arXiv · 1704.00155

The sign of the dipole-dipole potential by axion exchange

Ryuji Daido·Fuminobu Takahashi
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Abstract

We calculate a dipole-dipole potential between fermions mediated by a light pseudoscalar, axion, paying a particular attention to the overall sign. While the sign of the potential is physical and important for experiments to discover or constrain the axion coupling to fermions, there is often a sign error in the literature. The purpose of this short note is to clarify the sign issue of the axion-mediated dipole-dipole potential. As a by-product, we find a sign change of the dipole-dipole potenital due to the different spin of the mediating particle.

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Ryuji Daido, Fuminobu Takahashi. 2017-04-01. The sign of the dipole-dipole potential by axion exchange. https://doi.org/10.1016/j.physletb.2017.06.027

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