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arXiv · 2410.19902

A Universal Bound on QCD Axions from Supernovae

Konstantin Springmann·Michael Stadlbauer·Stefan Stelzl·Andreas Weiler
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Abstract

We identify a new production channel for QCD axions in supernova environments that contributes to axion emissivity for all models solving the strong CP problem. This channel arises at tree-level from a shift-symmetry-breaking operator constructed at next-to-leading order in Chiral Perturbation Theory. In scenarios where model-dependent derivative couplings to nucleons are absent, this sets the strongest model-independent constraint on the axion mass, improving on existing bounds by two orders of magnitude.

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Konstantin Springmann, Michael Stadlbauer, Stefan Stelzl, Andreas Weiler. 2024-10-25. A Universal Bound on QCD Axions from Supernovae. https://arxiv.org/abs/2410.19902

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