Charged-particle decay and suppression of primordial power on small scales.
Charged-particle decay and suppression of primordial power on small scales.
复制标题
带电粒子衰变和小尺度原始能量的抑制。
DOI：
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发表时间：
2003
影响因子：
8.6
通讯作者：
M. Kamionkowski
中科院分区：
文献类型：
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作者：
K. Sigurdson;M. Kamionkowski
我们研究了小尺度功率谱的抑制，由于带电物质的衰变到暗物质之前的重组。在衰变之前，带电粒子耦合到光子-重子流体并参与其声学振荡。然而，在这些带电粒子衰变为中性暗物质之后，光子-重子流体仅与新产生的暗物质引力耦合。这通常导致在衰变之前进入视界的长度尺度上的功率抑制。对于大约3.5年的衰变时间，这导致抑制功率在亚星系尺度上，使观测到的星系子结构的数量与观测一致。如果暗物质是纯粹的引力相互作用，例如超对称模型中的引力子或具有普适额外维度的模型中的大质量卡鲁扎-克莱因引力子，那么衰变时间可能为几年。
We study the suppression of the small-scale power spectrum due to the decay of charged matter to dark matter prior to recombination. Prior to decay, the charged particles couple to the photon-baryon fluid and participate in its acoustic oscillations. However, after these charged particles decay to neutral dark matter, the photon-baryon fluid is coupled only gravitationally to the newly created dark matter. This generically leads to suppression of power on length scales that enter the horizon prior to decay. For decay times of approximately 3.5 yr this leads to suppression of power on subgalactic scales, bringing the observed number of galactic substructures in line with observation. Decay times of a few years are possible if the dark matter is purely gravitationally interacting, such as the gravitino in supersymmetric models or a massive Kaluza-Klein graviton in models with universal extra dimensions.