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arXiv · 1911.08472

Axion Fragmentation

Nayara Fonseca·Enrico Morgante·Ryosuke Sato·Géraldine Servant
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Abstract

We investigate the production of axion quanta during the early universe evolution of an axion-like field rolling down a wiggly potential. We compute the growth of quantum fluctuations and their back-reaction on the homogeneous zero-mode. We evaluate the transfer of kinetic energy from the zero mode to the quantum fluctuations and the conditions to decelerate the axion zero-mode as a function of the Hubble rate, the slope of the potential, the size of the barriers and the initial field velocity. We discuss how these effects impact the relaxion mechanism.

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Nayara Fonseca, Enrico Morgante, Ryosuke Sato, Géraldine Servant. 2019-11-19. Axion Fragmentation. https://doi.org/10.1007/jhep04(2020)010

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