In this paper, we explore an extension of the classical non-standard cosmological scenario in which the new field, ϕ, which interacts with the radiation component in the early universe, experiences dissipative processes in the form of a bulk viscosity. Assuming an interaction term given by Γ _ϕ ρ _ϕ , where Γ _ϕ accounts for the decay rate of the field and ρ _ϕ corresponds to its energy density, and a bulk viscosity according to the expression ξ=ξ ₀ ρ _ϕ ϕ^1/2 in the framework of Eckart's theory, we apply this novel non-standard cosmology to study the parameters space for WIMPs Dark Matter candidate production. This parameter space shows deviations from the classical non-standard cosmological scenario, obtaining new regions to search for this candidate. In particular, for certain combinations of the free parameters, we found large regions in which the model can establish the DM and reproduce the current observable relic density.

中文翻译：

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块状粘性非标准宇宙学中的 WIMP 暗物质


在本文中，我们探讨了经典非标准宇宙学情景的扩展，其中与早期宇宙中的辐射分量相互作用的新场 φ 以体粘度的形式经历耗散过程。假设Γ _φ ρ _φ 给出的相互作用项，其中 _{Γ φ} 表示场的衰减率，ρ _φ 对应于其能量密度，并且根据表达式 ξ=ξ₀ρ _φ φ^1/2 在 Eckart 理论的框架内，我们应用这种新颖的非标准宇宙学来研究 WIMP 暗物质候选物质产生的参数空间。这个参数空间显示了与经典非标准宇宙学情景的偏差，获得了新的区域来搜索这个候选者。特别是，对于自由参数的某些组合，我们发现模型可以在大区域建立 DM 并再现当前可观测的遗迹密度。