The QCD Axion Window and Low Scale Inflation

Autor:	Takahashi, Fuminobu, Yin, Wen, Guth, Alan H.
Rok vydání:	2018
Předmět:	High Energy Physics - Phenomenology General Relativity and Quantum Cosmology High Energy Physics - Experiment
Zdroj:	Phys. Rev. D 98, 015042 (2018)
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevD.98.015042
Popis:	We show that the upper bound of the classical QCD axion window can be significantly relaxed for low-scale inflation. If the Gibbons-Hawking temperature during inflation is lower than the QCD scale, the initial QCD axion misalignment angle follows the Bunch-Davies distribution. The distribution is peaked at the strong CP conserving minimum if there is no other light degree of freedom contributing to the strong CP phase. As a result, the axion overproduction problem is significantly relaxed even for an axion decay constant larger than $10^{12}$GeV. We also provide concrete hilltop inflation models where the Hubble parameter during inflation is comparable to or much smaller than the QCD scale, with successful reheating taking place via perturbative decays or dissipation processes. Comment: 14 pages, 3 figures; v3:a version to appear in PRD
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1805.08763 Zobrazit plný text záznamu View this record from Arxiv