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arXiv 0902.3662hep-phastro-ph.COgr-qchep-th
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中性子暗物质星不可能存在

Neutralino dark matter stars can not exist

De-Chang Dai, Dejan Stojkovic

摘要:

最近的“宇宙计划”的暗物质浓度的观察,没有普通物质在同一个地方的动机,我们研究的问题,由纯暗物质紧凑的对象的存在。我们假设暗物质是中性伴子,并比较了它的弹性和湮灭截面。我们发现这两个截面的数量级相同。这个结果有一个直接而重要的推论,即组成致密物体的中性伴子不能达到热平衡。为了证实我们的论点,我们通过求解Oppenheimer-Escheroff方程,构造了一个由纯中性伴子构成的恒星模型。我们明确地表明,费米压强所支持的热平衡条件在恒星内部永远不会得到满足。这种中性伴子态不能用费米-狄拉克分布来描述。因此,一个稳定的中性伴子星,这是由费米压力支持,不可能存在。我们还估计了一颗稳定的恒星不可能含有超过几个质量的中性伴子,大部分质量必须是标准模型粒子的形式。

英文摘要:

Motivated by the recent "Cosmos Project" observation of dark-matter concentrations with no ordinary matter in the same place, we study the question of the existence of compact objects made of pure dark matter. We assume that the dark matter is neutralino, and compare its elastic and annihilation cross sections. We find that the two cross sections are of the same order of magnitude. This result has a straightforward and important consequence that neutralinos comprising a compact object can not achieve thermal equilibrium. To substantiate our arguments, by solving Oppenheimer-Volkoff equation we constructed a model of the star made of pure neutralinos. We explicitly showed that the condition for the thermal equilibrium supported by the Fermi pressure is never fulfilled inside the star. This neutralino state can not be described by the Fermi-Dirac distribution. Thus, a stable neutralino star, which is supported by the Fermi pressure, can not exist. We also estimated that a stable star can not contain more than a few percents of neutralinos, most of the mass must be in the form of the standard model particles.

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。

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