行星际结构与非稳态准垂直激波相互作用中的粒子加速

Collisionless shock is a common physical phenomenon in space physics, plasma physics and astrophysics. They are commonly believed to be important sources for high-energy particles, such as Solar Energetic Particles (SEPs), Anomalous Cosmic Rays (ACRs)，Galactic Cosmic Rays (GCRs) and for Hot Flow Anomalous (HFA). Previous space observations, laboratory experiments, numerical simulations evidenced that supercritical, quasi-perpendicular shocks are nonstationary. One- and two- dimensional PIC simulations are performed in order to study the ion acceleration by the interaction between two kinds of interplanetary structure-the current sheet and Alfvén waves, and nonstationary shocks. Recent observations by Voyager indicate that high-energy particles at collisionless shock are highly associated with crossings of the heliospheric current sheet. So we concentrate on the impact of the inclination of the current sheet relative to the shock normal on the ions acceleration, the nonlinear evolution of the shock front and the HFA formation at nonstationary quasi-perpendicular shocks. Furthermore, previous simulations demonstrate that the upstream Alfvén waves can penetrate through the stationary perpendicular shock front. Obvious ripples, which can intensively affect the ion acceleration, in the shock front are found. Based on the findings, we continue to study the ion acceleration mechanism in the colliding plasma structures: Alfvén waves and nonstationary shocks.

无碰撞激波是空间物理、等离子体物理和天体物理中常见的物理现象。激波加速被普遍认为是产生太阳高能粒子（SEPs）、反常宇宙线（ACRs）、银河宇宙线（GCRs）等高能粒子和热流异常(HFA)的重要机制。无论观测、等离子体试验、还是数值模拟都已证实超临界准垂直激波是非稳态的。我们利用一维和二维全粒子模拟程序，研究非稳态激波与两种行星际结构-电流片和阿尔芬波相互作用中的离子加速。最近旅行者号探测器的观测表明，日球层电流片和无碰撞激波相互作用会严重影响高能离子的产生。因此，我们着重分析非稳态准垂直激波条件下，电流片与激波面法向的夹角对离子加速、激波面非线性演化和热流异常的影响。另外，前人的模拟研究表明上游阿尔芬波能够穿透稳态激波，并引起激波面的涟波，这也会对离子的加速过程造成很大的影响。我们将延续前人的工作，进一步研究非稳态激波和阿尔芬波相互作用过程中的离子加速机制。

无碰撞激波是空间物理、等离子体物理和天体物理中常见的物理现象。激波加速被普遍认为是产生太阳高能粒子（SEPs）、反常宇宙线（ACRs）、银河宇宙线（GCRs）等高能粒子和热流异常(HFA)的重要机制。无论观测、等离子体试验、还是数值模拟都已证实超临界准垂直激波是非稳态的。我们利用一维和二维全粒子模拟程序，研究非稳态激波与两种行星际结构-电流片和阿尔芬波相互作用中的离子加速，以及新生粒子对激波耗散机制的影响。主要的研究成果发表在等离子体物理、天体物理、天体物理快报上。我们证明了我们数值模拟程序的有效性和广泛的应用前景。