In this work, we propose a powerful probe of neutrino effects on the large-scale structure (LSS) of the Universe, i.e., Minkowski functionals (MFs). The morphology of LSS can be fully described by four MFs. This tool, with strong statistical power, is robust to various systematics and can comprehensively probe all orders of N-point statistics. By using a pair of high-resolution N-body simulations, for the first time, we comprehensively studied the subtle neutrino effects on the morphology of LSS. For an ideal LSS survey of volume $\sim1.73$ Gpc$^3$/$h^3$, neutrino signals are mainly detected from void regions with a significant level up to $\thicksim 10σ$ and $\thicksim 300σ$ for CDM and total matter density fields, respectively. This demonstrates its enormous potential for much improving the neutrino mass constraint in the data analysis of up-coming ambitious LSS surveys.
Sensitivity of Neutrino Mass Experiments to the Cosmic Neutrino Background
KATRIN中微子实验是下一代氚β衰变实验,旨在测量90% C. L时电子中微子的质量优于200 meV。由于其强烈的氚源,KATRIN也可以作为中微子捕获过程的可能目标,νe +3 H \to 3 He + + e-。后一个过程没有能量阈值,对宇宙中微子背景(CνB)很敏感。本文探讨了KATRIN实验对残余中微子密度的潜在敏感性。KATRIN实验对CνB超密度比为2.0 × 10^9(超过标准一致性模型预测值(在90% C. L.))的情况很敏感,探讨某些推测性宇宙学模型的有效性
Geometry and Morphology of the Cosmic Web: Analyzing Spatial Patterns in the Universe
我们回顾了宇宙网络的分析手段的基础上使用的Delaunay和Voronoi镶嵌的广泛的工具集。宇宙网络是一种突出而普遍的泡沫状模式,物质在其中以几兆秒差距到一百多兆秒差距的尺度组织起来。首先,我们描述了Delaunay Tessellation Field Estimation(DTFE)。DTFE形式主义恢复宇宙物质分布的层次性和各向异性形态。多尺度形态滤波器(MMF)使用DTFE密度场来提取不同的形态元素-细丝,薄片和簇-基于ScaleSpace分析,该分析在一系列尺度上搜索这些形态。随后,我们讨论了分水岭空洞探测器(WVF),它调用离散分水岭变换来识别宇宙物质分布中的空洞。退伍军人联合会能够确定空洞的位置、大小和形状。分水岭变换也是SpineWeb分析宇宙物质分布的关键要素。它允许通过识别奇点和相应的分界线来确定宇宙物质密度场中的脊和连接壁。最后,我们描述的概念Alphashapes评估的宇宙物质分布的拓扑结构。
The Hot Big Bang model predicts the existence of a \emph{cosmic neutrino background}. The number of particles and anti-particles in this primordial bath of neutrinos can be different -- a memory of processes that took place at very early epochs. If neutrinos were massless, this asymmetry would not change once neutrinos froze out. However, in the case of massive particles, the asymmetry is not protected by conservation laws and can get erased via helicity-flipping scatterings off matter inhomogeneities. We evaluate this helicity-flipping rate and demonstrate that if relic lepton asymmetry ever …
We explore the potential of measurements of cosmological effects, such as neutrino spectral distortions from the neutrino decoupling and neutrino clustering in our Galaxy, via cosmic neutrino capture on tritium. We compute the precise capture rates of each neutrino species including such cosmological effects to probe them. These precise estimates of capture rates are also important in that the would-be deviation of the estimated capture rate could suggest new neutrino physics and/or a non-standard evolution of the universe. In addition, we discuss the precise differences between the capture ra…
Neutrinos might interact among themselves through forces that have so far remained hidden. Throughout the history of the Universe, such \emph{secret} interactions could lead to scatterings between the neutrinos from supernova explosions and the non-relativistic relic neutrinos left over from the Big Bang. Such scatterings can boost the cosmic neutrino background (C$ν$B) to energies of ${\cal O}$(MeV), making it, in principle, observable in experiments searching for the diffuse supernova neutrino background. Assuming a model-independent, but flavor universal, four-Fermi interaction, we determin…
The Cosmic Neutrino Background is within Reach of Future Neutrino Telescopes
Massachusetts Institute of Technology(麻省理工学院);Harvard University(哈佛大学);Virginia Tech(弗吉尼亚理工大学);Institute of Science Tokyo(东京科学大学);The University of Tokyo(东京大学)