Self-interacting dark matter has been proposed to explain the apparent mass deficit in astrophysical small-scale halos, while observations from galaxy clusters suggest that the corresponding cross section depends on the velocity. Accounting for this is often believed to be highly model-dependent with studies mostly focusing on scenarios with light mediators. Based on the effective-range formalism, in this work we point out a model-independent approach which accurately approximates the velocity dependence of the self-interaction cross section with only two parameters. We illustrate how this parameterization can be simultaneously interpreted in various well-motivated scenarios, including self-interactions induced by Yukawa forces, Breit-Wigner resonances and bound states. We investigate the astrophysical implications and discuss how the approximation can be improved in certain special regimes where it works poorly.

中文翻译：

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暗物质自相互作用的实用且一致的参数化

已经提出自相互作用暗物质来解释天体物理小尺度晕中的明显质量缺陷，而来自星系团的观测表明相应的横截面取决于速度。对此的解释通常被认为是高度依赖于模型的，研究主要集中在光介质的场景上。基于有效范围形式主义，在这项工作中，我们指出了一种独立于模型的方法，该方法仅用两个参数准确地近似自相互作用截面的速度依赖性。我们说明了如何在各种动机良好的场景中同时解释这种参数化，包括由汤川力、Breit-Wigner 共振和束缚态引起的自相互作用。