Seismic observations of a slowdown in P wave velocity at the base of Earth's outer core suggest the presence of a stably-stratified region known as the F-layer. This raises an important question: how can light elements that drive the geodynamo pass through the stably-stratified layer without disturbing it? We consider the F-layer as a slurry containing solid particles dispersed within the liquid iron alloy that snow under gravity towards the inner core. We present a regime diagram showing how the dynamics of the slurry F-layer change upon varying the key parameters: Péclet number ($Pe$), the ratio between advection and chemical diffusion; Stefan number ($St$), the ratio between sensible and latent heat; and Lewis number ($Le$), the ratio between thermal and chemical diffusivity. We obtain four regimes corresponding to stable, partially stable, unstable and no slurries. No slurry is found when the heat flow at the base of the layer exceeds the heat flow at the top, while a stably-stratified slurry arises when advection overcomes thermal diffusion ($Pe \gtrsim Le$) that exists over a wide range of parameters relevant to the Earth's core. Our results estimate that a stably-stratified F-layer gives a maximum inner-core boundary (ICB) body wave density jump of $Δρ_\textrm{bod} \leq 534 \ \mathrm{kg} \mathrm{m}^{-3}$ which is compatible with the lower end of the seismic observations where $280 \leq Δρ_\textrm{bod} \leq 1,100 \ \mathrm{kg} \mathrm{m}^{-3}$ is reported in the literature. With high thermal conductivity the model predicts an inner core age between $0.6$ and $1.2 \ \mathrm{Ga}$, which is consistent with other core evolution models. Our results suggest that a slurry model with high core conductivity predicts geophysical properties of the F-layer and core that are consistent with independent seismic and geodynamic calculations.
Recovery of 150-250 MeV Cosmic Ray Proton Intensities Between 2004-2010 as Measured Near the Earth, at Voyager 2 and also in the Heliosheath at Voyager 1 - A Two Zone Heliosphere
Transport properties for liquid silicon-oxygen-iron mixtures at Earth's core conditions
我们报告的热和导电性的两种液体硅-氧-铁混合物（Fe $_{0.82}$ Si $_{0.10}$ O $_{0.08}$和Fe $_{0.79}$ Si $_{0.08}$ O $_{0.13}$），代表地球的外核的组成在相关的压力-温度条件下，从密度泛函理论计算与Kubo-Greenwood公式。我们发现导热系数$k$ =100（160）W m $^{-1}$ K $^{-1}$，以及外核顶部（底部）的电导率$σ= 1.1 (1.3) \times 10^6 Ω^{-1}$ m $^{-1}$。这些新的数值比以前的估计高出2至3倍，对我们理解地球的热历史和地球磁场的功能，包括整个地核的快速冷却速度或地核中高水平的放射性元素具有深远的影响。我们还展示了一些混合物的结构和动力学性质的结果，包括部分径向分布函数，均方位移，粘度和声速。
Recovery of 150-250 MeV/nuc Cosmic Ray Helium Nuclei Intensities Between 2004-2010 Near the Earth, at Voyager 2 and Voyager 1 in the Heliosheath - A Two Zone Helioshpere
Interplay of non-standard interactions and Earth's composition in atmospheric neutrino oscillations
Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México（墨西哥国立自治大学核科学研究所）；Instituto de Física de Mar del Plata (IFIMAR), CONICET, UNMDP, Departamento de Física, Universidad Nacional de Mar del Plata（马德普拉塔大学物理系马德普拉塔物理研究所（CONICET））
20-125 mev/nuc cosmic ray carbon nuclei intensities between 2004-2010 in solar cycle #23 as measured near the earth, at voyager 2 and also in the heliosheath at voyager 1 - modulation in a two zone heliospehre
GRACE -- gravity data for understanding the deep Earth's interior
虽然GRACE空间飞行任务观测到的时间重力变化的主要原因是地球表面响应气候和人为强迫而发生的水团重新分布（例如，陆地水文、海洋质量、冰川和冰盖质量的变化），固体地球质量的再分布也被这些观测记录下来。特别是冰川均衡调整（GIA）或地幔对末次冰消作用的粘性响应。然而，直到最近才发现重力数据还包含了外核内部流动的特征及其对核幔边界的影响。在GRACE观测中探测地球深部的过程提供了一个令人兴奋的机会，可以提供关于核幔界面动力学的额外见解。本文介绍GRACEFUL（Gravimetry，mAgnetism and CorE Flow）计划的一个方面，即利用重力场资料了解地球流体核和核幔边界内的动力学过程的可能性，以及地磁场变化所提供的动力学过程。
Effect of thermal conductivity on the simultaneous formation of a stable region at the top of Earth's core and magnetic field generation over four billion years
