Dark matter search in dwarf irregular galaxies with theFermiLarge Area Telescope,Physical Review D

当前位置： X-MOL 学术 › Phys. Rev. D › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Dark matter search in dwarf irregular galaxies with theFermiLarge Area Telescope
Physical Review D ( IF 4.6 ) Pub Date : 2021-10-21 , DOI: 10.1103/physrevd.104.083026
V. Gammaldi ₁ , J. Pérez-Romero ₁ , J. Coronado-Blázquez ₁ , M. Di Mauro ₂ , E. V. Karukes ₃ , M. A. Sánchez-Conde ₁ , P. Salucci _{4,

5}

Affiliation

We analyze 11 years of Fermi-Large Area Telescope (LAT) data corresponding to the sky regions of seven dwarf irregular (dIrr) galaxies. DIrrs are dark matter (DM)-dominated systems, proposed as interesting targets for the indirect search of DM with gamma rays. The galaxies represent interesting cases with a strong disagreement between the density profiles (core versus cusp) inferred from observations and numerical simulations. In this work, we addressed the problem by considering two different DM profiles, based on both the fit to the rotation curve (in this case, a Burkert cored profile) and results from

N

-body cosmological simulations (i.e., Navarro-Frenk-White cuspy profile). We also include halo substructure in our analysis, which is expected to boost the DM signal by a factor of 10 in halos such as those of dIrrs. For each DM model and dIrr, we create a spatial template of the expected DM-induced gamma-ray signal to be used in the analysis of Fermi-LAT data. No significant emission is detected from any of the targets in our sample. Thus, we compute upper limits on the DM annihilation cross section versus mass parameter space. Among the seven dIrrs, we find IC10 and NGC6822 to yield the most stringent individual constraints, independently of the adopted DM profile. We also produce combined DM limits for all objects in the sample, which turn out to be dominated by IC10 for all DM models and annihilation channels, i.e.,

b \bar{b}

τ^{+} τ^{-}

, and

W^{+} W^{-}

. The strongest constraints are obtained for

b \bar{b}

and are at the level of

⟨ σ v ⟩ \sim 7 \times 10^{- 26} {cm}^{3} s^{- 1}

m_{χ} \sim 6 GeV

. Though these limits are a factor of

\sim 3

higher than the thermal relic cross section at low weakly interacting massive particles masses, they are independent from and complementary to those obtained by means of other targets.

中文翻译：

用费米大面积望远镜在矮不规则星系中搜索暗物质

我们分析了 11 年的费米大面积望远镜 (LAT) 数据，这些数据对应于七个矮不规则 (dIrr) 星系的天空区域。DIrrs 是暗物质 (DM) 主导的系统，被提议作为用伽马射线间接搜索 DM 的有趣目标。这些星系代表了有趣的案例，在从观测和数值模拟中推断出的密度剖面（核心与尖顶）之间存在强烈分歧。在这项工作中，我们通过考虑两个不同的 DM 轮廓来解决这个问题，基于对旋转曲线的拟合（在这种情况下，一个 Burkert 核心轮廓）和结果

N

- 天体宇宙学模拟（即 Navarro-Frenk-White 尖顶剖面）。我们还在我们的分析中包括了光晕子结构，它有望将 DM 信号在光晕（例如 dIrrs 的光晕）中提高 10 倍。对于每个 DM 模型和 dIrr，我们创建了一个预期的 DM 诱导伽马射线信号的空间模板，用于分析费米-LAT 数据。我们样本中的任何目标都没有检测到显着的排放。因此，我们计算 DM 湮灭截面与质量参数空间的上限。在七个 dIrrs 中，我们发现 IC10 和 NGC6822 产生最严格的个体约束，与采用的 DM 配置文件无关。我们还为样本中的所有对象生成了组合 DM 限制，结果证明对于所有 DM 模型和湮灭通道，IC10 占主导地位，即，