Barriga-Carrasco Manuel D
ETSI Industriales, Universidad de Castilla-La Mancha, E-13071 Ciudad Real, Spain.
Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Oct;82(4 Pt 2):046403. doi: 10.1103/PhysRevE.82.046403. Epub 2010 Oct 25.
In this work, we present a dielectric function including the three conservation laws (density, momentum and energy) when we take into account electron-electron collisions in a plasma at any degeneracy. This full conserving dielectric function (FCDF) reproduces the random phase approximation (RPA) and Mermin ones, which confirms this outcome. The FCDF is applied to the determination of the proton stopping power. Differences among diverse dielectric functions in the proton stopping calculation are minimal if the plasma electron collision frequency is not high enough. These discrepancies can rise up to 2% between RPA values and the FCDF ones, and to 8% between the Mermin ones and FCDF ones. The similarity between RPA and FCDF results is not surprising, as all conservation laws are also considered in RPA dielectric function. Even for plasmas with low collision frequencies, those discrepancies follow the same behavior as for plasmas with higher frequencies. Then, discrepancies do not depend on the plasma degeneracy but essentially do on the value of the plasma collision frequency.
在这项工作中，当我们考虑任意简并度下等离子体中的电子 - 电子碰撞时，我们提出了一个包含三个守恒定律（密度、动量和能量）的介电函数。这个全守恒介电函数（FCDF）重现了随机相位近似（RPA）和默明介电函数，这证实了这一结果。FCDF被应用于质子阻止本领的确定。如果等离子体电子碰撞频率不够高，在质子阻止计算中不同介电函数之间的差异很小。这些差异在RPA值和FCDF值之间可高达2%，在默明介电函数值和FCDF值之间可高达8%。RPA和FCDF结果之间的相似性并不奇怪，因为在RPA介电函数中也考虑了所有守恒定律。即使对于碰撞频率较低的等离子体，这些差异与碰撞频率较高的等离子体具有相同的行为。因此，差异不取决于等离子体的简并度，而主要取决于等离子体碰撞频率的值。
