2025-11-25 中国科学院(CAS)

Evolution of matter density in the context of large-scale filamentary structures. In the IDE I model, the dark matter halos are loose and elongated, whereas in the IDE II model, they are compact and round. (Image by ZHANG Jiajun)
<関連情報>
- https://english.cas.cn/newsroom/research_news/phys/202511/t20251125_1133227.shtml
- https://journals.aps.org/prd/abstract/10.1103/lq8t-gw3m
相互作用する暗黒物質におけるハロースピンと配向 暗黒エネルギー宇宙論 Halo spin and orientation in interacting dark matter dark energy cosmology
Guandi Zhao,Jiajun Zhang, Peng Wang, and Ji Yao
Physical Review D Published: 19 November, 2025
DOI: https://doi.org/10.1103/lq8t-gw3m
Abstract
In recent years, the interaction between dark matter (DM) and dark energy (DE) has become a topic of interest in cosmology. Interacting dark matter dark energy (IDE) models have a substantial impact on the formation of cosmological large-scale structures, which serve as the environment for DM halo evolution. This impact can be examined through the shape and spin orientation of halos in numerical simulations incorporating IDE effects. In our work, we used the N-body simulation pipeline me-gadget to simulate and study the halo spin and orientation in IDE models. We found that, in models where DM transfers into DE (IDE I), the alignment of halo shapes with the surrounding tidal field is enhanced compared to ΛCDM, while the alignment of halo spins with the tidal field is decreased compared to the ΛCDM. Conversely, in models where DE transfers into DM (IDE II), the opposite occurs. We have provided fitted functions to describe these alignment signals. Our study provides the foundation for more accurate modeling of observations in future surveys such as China Space Station Telescope.


