We study the fluctuations in the brightness temperature of 21-cm signal δT21 at the dark ages (z ∼ 100) with a dark matter (DM) candidate in Inert Doublet Model (IDM). We then explore the effects of different fractions of IDM DM on δT21 signal. The IDM DM masses are chosen in few tens of GeV region as well as in the high mass region beyond 500 GeV. It has been observed that the δT21 signal is more sensitive in the DM mass range of 70–80 GeV. A lower bound on annihilation cross-section for this DM is also obtained by analyzing the δT21 signal. This is found to lie within the range 6.5 × 10−29 cm3/s ≤〈σv〉≤ 4.88 × 10−26 cm³/s for the IDM DM mass range 10 GeV ≤ mχ ≤ 990 GeV.

中文翻译：

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在黑暗时代的 21 厘米宇宙学背景下，惰性双峰模型中暗物质湮灭截面的界限

我们研究了21厘米信号的亮温波动δ吨21在黑暗时代（z ～ 100) 与惰性双峰模型 (IDM) 中的暗物质 (DM) 候选者。然后我们探讨不同部分的 IDM DM 对δ吨21信号。IDM DM 质量选择在几十 GeV 区域以及超过 500 GeV 的高质量区域。据观察，δ吨21信号在 70-80 GeV 的 DM 质量范围内更敏感。通过分析δ吨21信号。发现这在范围内6.5 × 10-29 厘米3/s ≤〈σv〉≤ 4.88 × 10-26cm ³ /s 用于 IDM DM 质量范围 10 GeV ≤ 米χ ≤ 990锗钒。