The effect of turbulent kinetic energy on inferred ion temperature from neutron spectra
The effect of turbulent kinetic energy on inferred ion temperature from neutron spectra
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DOI：
10.1063/1.4885342
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发表时间：
2014-07
影响因子：
2.2
通讯作者：
T. Murphy
中科院分区：
文献类型：
--
作者：
T. Murphy
测量氘 (DD) 或氘氚 (DT) 等离子体聚变产生的中子的能谱宽度是确定惯性约束聚变 (ICF) 内爆中离子温度的常用方法。在具有麦克斯韦离子能量分布的等离子体中，中子能量的扩散源自反应离子对的质心速度的热扩散。 ICF 中的流体速度与质心速度大小相似，可能导致中子能谱进一步展宽，从而导致离子温度的错误推断。反应等离子体的运动会对 DD 和 DT 中子产生不同的影响，导致从两个反应推断出的离子温度不一致。这种效应可能是导致过去几十年观察到的离子温度高于模拟预期、离子温度与观察到的产率不一致以及在同一内爆中从 DD 和 DD 测量到不同温度的原因之一。
Measuring the width of the energy spectrum of fusion-produced neutrons from deuterium (DD) or deuterium-tritium (DT) plasmas is a commonly used method for determining the ion temperature in inertial confinement fusion (ICF) implosions. In a plasma with a Maxwellian distribution of ion energies, the spread in neutron energy arises from the thermal spread in the center-of-mass velocities of reacting pairs of ions. Fluid velocities in ICF are of a similar magnitude as the center-of-mass velocities and can lead to further broadening of the neutron spectrum, leading to erroneous inference of ion temperature. Motion of the reacting plasma will affect DD and DT neutrons differently, leading to disagreement between ion temperatures inferred from the two reactions. This effect may be a contributor to observations over the past decades of ion temperatures higher than expected from simulations, ion temperatures in disagreement with observed yields, and different temperatures measured in the same implosion from DD an...