The QCD axion, precisely
Abstract
We show how several properties of the QCD axion can be extracted at high precision using only first principle QCD computations. By combining NLO results obtained in chiral perturbation theory with recent Lattice QCD results the full axion potential, its mass and the coupling to photons can be reconstructed with percent precision. Axion couplings to nucleons can also be derived reliably, with uncertainties smaller than ten percent. The approach presented here allows the precision to be further improved as uncertainties on the light quark masses and the effective theory couplings are reduced. We also compute the finite temperature dependence of the axion potential and its mass up to the crossover region. For higher temperature we point out the unreliability of the conventional instanton approach and study its impact on the computation of the axion relic abundance.
Keywords
Cite
@article{arxiv.1511.02867,
title = {The QCD axion, precisely},
author = {Giovanni Grilli di Cortona and Edward Hardy and Javier Pardo Vega and Giovanni Villadoro},
journal= {arXiv preprint arXiv:1511.02867},
year = {2017}
}
Comments
38 pages, 6 figures. v2: Discussion in sec. 2.4 simplified, fig.6 corrected, published version