Blackman D R, Nuter R, Korneev Ph, Tikhonchuk V T
Mechanical and Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093-0411, USA.
CELIA, University of Bordeaux, CNRS, CEA, 33405 Talence, France.
Phys Rev E. 2020 Sep;102(3-1):033208. doi: 10.1103/PhysRevE.102.033208.
We present, using three-dimensional particle-in-cell simulations, an observation that orbital angular momentum (OAM) is transferred to resonant electrons proportionally to longitudinal momentum when Laguerre-Gaussian plasma waves are subjected to Landau damping. A higher azimuthal mode number leads to a larger net orbital angular momentum transfer to particles traveling close to the phase velocity of the plasma wave, implying a population of electrons that are orbiting the same center of rotation as the plasma wave. This observation has implications on magnetic field excitation as a result of the formation and damping of OAM plasma waves. The energy distributions of electrons in damping Laguerre-Gaussian plasma waves are significantly changed as a function of azimuthal mode number. This leads to larger numbers of lower energy particles tending towards a significant narrowing of the energy distribution of accelerated particles.
当拉盖尔 - 高斯等离子体波受到朗道阻尼时，轨道角动量（OAM）会按纵向动量比例转移到共振电子上。更高的方位模数会导致更大的净轨道角动量转移到接近等离子体波相速度传播的粒子上，这意味着存在一群与等离子体波围绕同一旋转中心轨道运行的电子。由于OAM等离子体波的形成和阻尼，这一观测结果对磁场激发有影响。在阻尼拉盖尔 - 高斯等离子体波中，电子的能量分布随方位模数显著变化。这导致大量低能粒子趋向于使加速粒子的能量分布显著变窄。
