2020/07/02 by Tianjun Li, Li, Tianjun
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2007.00874
openalex publication_date 2020/07/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The XENON1T excess can be explained by the Axion Like Particle (ALP) dark matter with mass around 2.5 keV. However, there are three problems needed to be solved: suppressing the coupling gaγ between the ALP and photon, and generating the proper coupling gae between the ALP and electron as well as the correct ALP mass. We propose three models to solve these problems. In our models, the gae couplings are produced by integrating out the vector-like leptons, and the correct ALP masses arise from high-dimensional operators. In the KSVZ axion model, the coupling gaγ can be suppressed by choosing proper sets of vector-like fermions, but we need some fine-tunings to obtain the ALP mass. Similarly, one can study the DFSZ axion model. In the Z8 and U(1)X models with approximate Pseudo-Nambu-Goldstone Bosons (PNGBs), the coupling gaγ is suppressed due to SU(3)C × U(1)\rm EM anomaly free. In the Z8 model, the PNGB mass can be generated naturally at the keV scale via the dimension-8 operator. To solve the PNGB quality problem in the Z8 model, we embed it into the model with U(1)X gauge symmetry.