AI 中文总结
该研究利用含Q球暗物质的玩具模型，提出Q球的相互作用可将暗物质晕中心尖峰扁平化，或能解释星系小尺度观测的相关张力及内轮廓多样性。
AI 中文摘要
冷碰撞暗物质成功解释了包括大尺度结构形成在内的诸多观测结果，但在星系小尺度上仍存在张力，最显著的是尖峰-核（cusp-core）问题、固定晕质量下内旋转曲线形状及中心密度的多样性。这些观测表明，额外的暗 sector 物理可能影响暗物质晕的内部结构，不过目前尚无普遍接受的解释。本文利用一个具代表性的玩具模型，证明相互作用暗物质Q球（由守恒荷稳定的非拓扑孤子）可提供暗物质晕尖峰扁平化的自然机制，或有助于解释观测到的暗物质晕内轮廓多样性。这些Q球在早期宇宙的暗 sector 中产生，会在暗物质晕的致密中心区域增长，且其相互作用截面随孤子质量增大而减小。该过程优先在暗物质晕中心发生，将大质量Q球储存的部分静质量能转化为相对论性暗 sector 粒子，从而修改内部质量密度轮廓。由此产生的与密度相关的自调节能量损失，为暗物质晕尖峰扁平化提供了动力学机制，同时使暗物质晕的外部区域基本不受影响。
英文摘要
Cold, collisionless dark matter successfully explains a wide range of observations, including the formation of large-scale structure. Nevertheless, tensions remain on small, galactic scales, most notably the cusp-core, or inner-mass-deficit, problem and the diversity of inner rotation-curve shapes and central densities at fixed halo mass. These observations suggest that additional dark-sector physics may affect the inner structure of halos, although no generally accepted explanation has yet emerged. Here, making use of a toy but representative model, we show that interacting dark-matter Q-balls -- non-topological solitons stabilized by a conserved charge -- can provide a natural mechanism for halo cusp flattening and may contribute to observed diversity of inner halo profiles. Produced in the early Universe in the dark sector, these Q-balls grow in the dense central regions of halos, while their interaction cross section decreases as the soliton mass increases. This process operates preferentially in halo centers, converting part of the rest-mass energy stored in massive Q-balls into relativistic dark-sector particles and thereby modifying the inner mass-density profile. The resulting density-dependent, self-regulating energy loss provides a dynamical mechanism for flattening halo cusps while leaving the outer halo largely unaffected.
Comments17 pages, 7 figures. Submitted to Journal of Cosmology and Astroparticle Physics
