arXiv 2408.160422024-08-28astro-ph.COastro-ph.GA

利用银河系卫星星系对$ν$MSM暗物质性质的约束

Constraints on the properties of $ν$MSM dark matter using the satellite galaxies of the Milky Way

Oliver Newton, Mark R. Lovell, Carlos S. Frenk, Adrian Jenkins, John C. Helly, Shaun Cole, Andrew J. Benson

备注：: 14 pages, six figures, two appendices. A repository of reduced scripts and data will be made available at https://github.com/Musical-Neutron/nuMSM_constraints. Submitted, comments welcome!
发表信息：: Mon Not R Astron Soc (2025) 3713-3727
DOI：: 10.1093/mnras/staf1223

阅读 PDF

arXiv 页面 ↗HTML 原文 ↗

AI总结：

本研究利用银河系卫星星系丰度约束$ν$MSM暗物质模型，以95%置信度排除惰性中微子质量≤1.4 keV（含重子效应时为≤4 keV），并发现卫星计数约束弱于X射线未探测约束。

摘要：

低质量星系为研究抑制小尺度暗物质结构丰度的模型中偏离标准宇宙学范式提供了有力工具。可用于比较不同模型的最简单指标之一是银河系卫星星系的丰度。可行的暗物质模型必须产生足够的次结构，以容纳观测到的银河系卫星数量。在此，我们仔细审视了中微子最小标准模型（$ν{\rm MSM}$）的预言，该模型是粒子物理标准模型的一个动机良好的扩展，其中惰性中微子暗物质的产生通过原初等离子体中的轻子不对称性得到共振增强。这一过程使该模型能够规避当前与非共振产生暗物质相关的约束。独立于星系形成物理的假设，我们以至少95%的置信度排除了所有惰性中微子静质量$M_{\rm s} \leq 1.4\\, {\rm keV}$的$ν{\rm MSM}$参数化。纳入重子过程的物理动机描述并模拟再电离效应加强了我们的约束，我们排除了所有$M_{\rm s} \leq 4\\, {\rm keV}$的$ν{\rm MSM}$参数化。与其他文献不同，我们的基准约束并未排除疑似3.55 keV X射线谱线（如果它确实由惰性中微子衰变产生）；然而，一些最受青睐的参数空间被排除。如果银河系卫星计数高于我们的假设，或者银河系晕质量小于$M^{\rm MW}_{200} = 8 \times 10^{11}\\, {\rm M_\odot}$，我们则排除$ν{\rm MSM}$作为3.55 keV过剩的来源。与其他工作相比，我们发现来自卫星计数的约束明显弱于X射线未探测所报告的约束。

英文摘要：

Low-mass galaxies provide a powerful tool with which to investigate departures from the standard cosmological paradigm in models that suppress the abundance of small dark matter structures. One of the simplest metrics that can be used to compare different models is the abundance of satellite galaxies in the Milky Way. Viable dark matter models must produce enough substructure to host the observed number of Galactic satellites. Here, we scrutinize the predictions of the neutrino Minimal Standard Model ($ν{\rm MSM}$), a well-motivated extension of the Standard Model of particle physics in which the production of sterile neutrino dark matter is resonantly enhanced by a lepton asymmetry in the primordial plasma. This process enables the model to evade current constraints associated with non-resonantly produced dark matter. Independently of assumptions about galaxy formation physics we rule out, with at least 95 per cent confidence, all parameterizations of the $ν{\rm MSM}$ with sterile neutrino rest mass, $M_{\rm s} \leq 1.4\, {\rm keV}$. Incorporating physically motivated prescriptions of baryonic processes and modelling the effects of reionization strengthen our constraints, and we exclude all $ν{\rm MSM}$ parameterizations with $M_{\rm s} \leq 4\, {\rm keV}$. Unlike other literature, our fiducial constraints do not rule out the putative 3.55 keV X-ray line, if it is indeed produced by the decay of a sterile neutrino; however, some of the most favoured parameter space is excluded. If the Milky Way satellite count is higher than we assume, or if the Milky Way halo is less massive than $M^{\rm MW}_{200} = 8 \times 10^{11}\, {\rm M_\odot}$, we rule out the $ν{\rm MSM}$ as the origin of the 3.55 keV excess. In contrast with other work, we find that the constraints from satellite counts are substantially weaker than those reported from X-ray non-detections.

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。

AI总结：

摘要：

英文摘要：

相关论文