Light QCD Axion Dark Matter from Double Level Crossings

Autor:	Li, Hai-Jun, Peng, Ying-Quan, Chao, Wei, Zhou, Yu-Feng
Rok vydání:	2023
Předmět:	High Energy Physics - Phenomenology Astrophysics - Cosmology and Nongalactic Astrophysics
Druh dokumentu:	Working Paper
Popis:	The even light QCD axion called the $Z_{\mathcal N}$ axion can both solve the strong CP problem and account for the dark matter (DM). We point out that the single and double level crossings can naturally take place in the mass mixing between the $Z_{\mathcal N}$ axion and axionlike particle (ALP). The first level crossing occurs much earlier than the QCD phase transition, while the second level crossing occurs exactly during the QCD phase transition if it exists. We also find that the single level crossing can transform into the double level crossings, depending on the ALP mass $m_A$ versus the zero-temperature $Z_{\mathcal N}$ axion mass $m_{a,0}$. Compared with the no level crossing case, the $Z_{\mathcal N}$ axion relic density can be suppressed in the single level crossing, and enhanced or suppressed in the double level crossings. Comment: 6 pages, 1 figure. Published in PLB
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2310.02126 Zobrazit plný text záznamu View this record from Arxiv