arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0901.4117hep-ph
收藏

不对称暗物质

Asymmetric Dark Matter

David E. Kaplan, Markus A. Luty, Kathryn M. Zurek

摘要:

我们考虑一类简单的模型,其中暗物质的残余密度由宇宙的重子不对称性决定。在这些模型中,在高温下产生的$B - L$不对称性被转移到暗物质中,该物质在$B - L$下带电。传递不对称性的相互作用在高于暗物质质量的温度下解耦,冻结在一个暗物质不对称的重子不对称性。这就解释了在5- 15 GeV范围内的暗物质中观察到的重子和暗物质密度之间的关系。暗物质的对称成分可以有效地湮灭为轻的赝标量希格斯粒子$a$,或者通过新的标量二重态的$t$通道交换。第一种可能性允许$h^0 \to aa$衰变,而第二种可能性则预测一个轻带电的类希格斯标量衰变为$τν$。在第一个模型中,直接探测可以来自希格斯交换,在第二个模型中,直接探测可以来自非零的磁矩。在超对称模型中,可能的LSP可以衰变成成对的暗物质粒子加上标准模型粒子,可能有位移的顶点。

英文摘要:

We consider a simple class of models in which the relic density of dark matter is determined by the baryon asymmetry of the universe. In these models a $B - L$ asymmetry generated at high temperatures is transfered to the dark matter, which is charged under $B - L$. The interactions that transfer the asymmetry decouple at temperatures above the dark matter mass, freezing in a dark matter asymmetry of order the baryon asymmetry. This explains the observed relation between the baryon and dark matter densities for dark matter mass in the range 5--15 GeV. The symmetric component of the dark matter can annihilate efficiently to light pseudoscalar Higgs particles $a$, or via $t$-channel exchange of new scalar doublets. The first possibility allows for $h^0 \to aa$ decays, while the second predicts a light charged Higgs-like scalar decaying to $τν$. Direct detection can arise from Higgs exchange in the first model, or a nonzero magnetic moment in the second. In supersymmetric models, the would-be LSP can decay into pairs of dark matter particles plus standard model particles, possibly with displaced vertices.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑