Near peak compression, inertial confinement fusion implosions release both deuterium–tritium (DT) fusion gamma rays and neutron induced gamma rays from carbon from the areal density of the remaining ablator shell. The gamma reaction history diagnostic makes a time resolved measurement of both. Across many recent implosions, the carbon gamma ray peak arrives systematically 11 ± 10 ps later compared to DT fusion burn. The timing shift is consistent with the carbon areal density increasing throughout the peak of the fusion burn, implying that the carbon portion of the capsule continues to converge. A model finds that the observed timing shift is consistent with a 4π averaged carbon ablator inward velocity of 80 μm/ns for the contemporary National Ignition Facility implosions. The timing shift is possibly related to the energy balance of the implosion, with the expectation that a high performing, igniting capsule would see the carbon gamma rays arrive before the DT fusion peak.

中文翻译：

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惯性约束聚变内爆下峰值熔合燃烧期间的时间分辨烧蚀剂面密度

在接近峰值压缩时，惯性约束聚变内爆会从其余烧蚀器壳的面密度中释放出氘-fusion（DT）聚变伽马射线和中子诱发的伽马射线。伽马反应历史诊断程序对这两者进行时间分辨测量。在所有最近的爆破中，与DT聚变燃烧相比，碳伽玛射线峰系统地晚11±10 ps到达。时间上的偏移与整个聚变燃烧峰中碳面密度的增加是一致的，这意味着胶囊的碳部分会继续收敛。模型认定，所观察到的定时偏移是具有4一致π平均碳消融器80向内的速度μ现代国家点火装置内爆的m / ns。时移可能与内爆的能量平衡有关，并期望高性能的点火舱会看到碳伽玛射线在DT聚变峰之前到达。