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arXiv · 1708.07521

The dark-matter axion mass

Vincent B. Klaer·Guy D. Moore
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Abstract

We evaluate the efficiency of axion production from spatially random initial conditions in the axion field, so a network of axionic strings is present. For the first time, we perform numerical simulations which fully account for the large short-distance contributions to the axionic string tension, and the resulting dense network of high-tension axionic strings. We find nevertheless that the total axion production is somewhat less efficient than in the angle-averaged misalignment case. Combining our results with a recent determination of the hot QCD topological susceptibility (Borsanyi et al 2016), we find that if the axion makes up all of the dark matter, then the axion mass is m_a = 26.2 +-3.4 micro-electron volts.

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Vincent B. Klaer, Guy D. Moore. 2017-08-24. The dark-matter axion mass. https://doi.org/10.1088/1475-7516%2F2017%2F11%2F049

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