多兆巴原级压力标尺揭示地核密度亏损
Density deficit of the Earth's core revealed by a multi-megabar primary pressure scale
AI总结：
本文通过联合测量铼的声速和密度建立多兆巴原级压力标尺，发现旧标尺在230吉帕高估压力至少20%，从而推断地球内核轻元素含量可能翻倍或温度更高。
摘要：
精确的压力标尺是理解行星内部的基本要求。在此，我们通过使用非弹性X射线散射和X射线衍射，在金刚石对顶砧中联合测量铼样品的声速和密度，建立了一个延伸至地核多兆巴压力的原级压力标尺。我们的标尺在每个实验压力范围内与先前的原级标尺和冲击Hugoniot数据吻合良好，并揭示先前的标尺在230吉帕处将实验室压力高估了至少20%。这表明地球内核中的轻元素含量（相对于铁的密度亏损）很可能是先前估计的两倍，或者地球内核温度远高于预期，或者两者兼而有之。
英文摘要：
An accurate pressure scale is a fundamental requirement to understand planetary interiors. Here, we establish a primary pressure scale extending to the multi-megabar pressures of the Earth's core, by combined measurement of the acoustic velocities and the density from a rhenium sample in a diamond anvil cell using inelastic x-ray scattering and x-ray diffraction. Our scale agrees well with previous primary scales and shock Hugoniots in each experimental pressure range, and reveals that previous scales have overestimated laboratory pressures by at least 20% at 230 gigapascals. It suggests that the light element content in the Earth's inner core (the density deficit relative to iron) is likely to be double what was previously estimated, or the Earth's inner core temperature is much higher than expected, or some combination thereof.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
