9 papers
Axion Mixing in the String Axiverse
Hai-Jun Li, Yu-Feng Zhou
String axiverse provides a fascinating and complex landscape for axion physics. The requirement in type IIB string axiverse models necessitates at least two axions to ensure the pr…
Completing Axion Double Level Crossings
Hai-Jun Li, Wei Chao, Huai-Ke Guo +1
In this work, we present the refinement of axion double level crossings within the context of multi-axion mass mixing, specifically focusing on cases where the number of axions exc…
On the Temperature Effects in QCD Axion Mass Mixing
Hai-Jun Li
In this work, we extend the QCD axion mass mixing in the early Universe and investigate the temperature effects in the mixing. We explore the scenario where two QC…
Mass Mixing between QCD Axions
Hai-Jun Li, Yu-Feng Zhou
We introduce a novel level crossing phenomenon in the mass mixing between the QCD axions, one canonical QCD axion and one axion. The level crossing can take place…
QCD Axion Dark Matter in the Dark Dimension
Hai-Jun Li
The recently proposed dark dimension scenario reveals that axions can be localized on the Standard Model brane, thereby predicting the quantum chromodynamics (QCD) axion decay cons…
Axion effects on gamma-ray spectral irregularities. II: Implications of EBL absorption
Hai-Jun Li, Wei Chao, Xiu-Hui Tan +1
The extragalactic background light (EBL) plays a crucial role in the propagation of high-energy particles throughout the Universe. In this work, we explore the impact of the EBL ab…