Halo-dependent Anharmonic Effects in Collective Excitation for Light Dark Matter Direct Detection

Summary

This study investigates the impact of anharmonic effects in collective excitation for light dark matter direct detection, considering the potential dark matter substructures indicated by the recent Gaia satellite observation.

Highlights

• The anharmonic effect in crystals is crucial for determining the dark matter-nucleus scattering cross-section, especially in the low dark matter mass region.
• The velocity distribution of the dark matter halo, affected by potential substructures, significantly influences the scattering event rate.
• The Gaia Sausage and S1 stream substructures exhibit a higher most probable speed and greater centralization, leading to an increased event rate and prevalence of multi-phonon events.
• The anharmonic effect becomes more significant for substructures with lower most probable speeds, such as S2a, S2b, and Rg5a.
• The expected sensitivity of future phonon detection experiments can be changed by a factor of 2-3 when considering anharmonic effects and DM substructures.
• The dark photon-mediated MeV-scaled DM model plays an important role in the phenomenology of DM detection.
• The atomic form factor is essential for considering the screening effect in DM detection.

Key Insights

• The anharmonic nature of crystals and DM substructures significantly impact the sub-GeV DM direct detection, and their effects should be considered in future experiments.
• The Gaia satellite observation reveals potential DM substructures that can affect the velocity distribution of the DM halo, leading to changes in the scattering event rate.
• The anharmonic effect is more pronounced in certain DM substructures, such as S2a, S2b, and Rg5a, due to their lower most probable speeds.
• The expected sensitivity of future phonon detection experiments can be improved by considering anharmonic effects and DM substructures, which can lead to a more accurate detection of DM.
• The dark photon-mediated MeV-scaled DM model is an important aspect of DM detection, and its effects should be considered in future experiments.
• The atomic form factor plays a crucial role in considering the screening effect in DM detection, which can impact the accuracy of DM detection.
• The consideration of anharmonic effects and DM substructures can lead to a more accurate detection of DM and a better understanding of its properties.

Mindmap

Citation

Guo, J., Wu, L., & Zhu, B. (2024). Halo-dependent Anharmonic Effects in Collective Excitation for Light Dark Matter Direct Detection (Version 1). arXiv. https://doi.org/10.48550/ARXIV.2412.18330