标题： 微分作用，例外而非规则——关于亚海王星内部完全混溶的证据 显示英文标题

标题： Differentiation, the exception not the rule -- Evidence for full miscibility in sub-Neptune interiors

摘要： 我们研究了硅酸盐、铁金属和氢之间非理想混合对亚海王星核心结构的影响，以及对超级地球、温海王星和冰巨行星的启示。 一种将我们对三个边界二元系统 MgSiO$_3$-H$_2$、MgSiO$_3$-Fe 和 Fe-H$_2$中的混溶性了解外推到三元成分空间的方法被用来推断该系统在相关温度和压力条件下的相平衡。 我们发现，尽管在浅层深度可以存在独立的硅酸盐和金属相，但在核心更深的地方，这些相会完全混溶，从而改变核心的密度结构。 假设大型岩石行星内部，无论是具有现存熔岩海洋位于富含 H$_2$的包层之下，还是由此类天体演化而来，均由分异的金属核心和覆盖的硅酸盐地幔组成，这与我们对这些天体相平衡的理解不一致。 显示英文摘要

摘要： We investigate the consequences of non-ideal mixing between silicate, iron metal, and hydrogen for the structures of the cores of sub-Neptunes with implications for super-Earths, warm Neptunes, and ice giants. A method of extrapolating what we know about the miscibility in the three bounding binary systems MgSiO$_3$-H$_2$, MgSiO$_3$-Fe, and Fe-H$_2$ to the ternary composition space is used to deduce the phase equilibria of this system at relevant temperature and pressure conditions. We find that while separate silicate and metal phases can exist at shallow depths, the phases become entirely miscible deeper in the cores, thus altering the density structure of the cores. The assumption that the interiors of large rocky planets, either with extant magma oceans beneath H$_2$-rich envelopes, or evolved from such bodies, are composed of a differentiated metal core overlain by a silicate mantle is inconsistent with our understanding of the phase equilibria of these bodies.