Axial Plasma Jets and their Interaction with and Production of Alfvén Waves

该奖项是根据NSF/DoE基础等离子体科学与工程合作伙伴关系联合招标NSF 08-589提交并审查的提案作出的。该奖项为研究生参加科学会议和本科生参与整体研究工作提供资金支持，该研究由美国能源部根据与加州大学洛杉矶分校的合同单独资助（科学报告#09ER55061）。该研究将使用加州大学洛杉矶分校独特的LAPD设备及其激光等离子体能力进行质量，能量和动量耦合的实验。迅速膨胀的等离子体变成大规模的磁化背景等离子体。使用激光，我们将产生场对准的等离子体流，可以从超音速到超级阿尔夫萨奇。该研究计划分为三个主要主题：1)等离子射流与压缩alfvsamn波的耦合，2)超音速流动尾迹和结构的产生，以及3)alfvsamn波与快速流动等离子体的相互作用。这些实验将由加州大学洛杉矶分校开发的最先进的PIC代码进行计算机模拟。该代码能够解析皮肤深度结构以及跟踪alfvsamic现象。alfvsamn波与运动等离子体的非线性相互作用一直是理论研究的主题，但从未在实验室实验中进行过探索。这项研究与地球磁尾现象、低β日冕洞内日冕羽膨胀现象有关，也可能与天体物理喷流有关。美国国家科学基金会对本科生参与的支持，通过将学生引入科学研究作为一种可能的职业道路，对他们进行早期培训，从而增加了更广泛的教育影响。

This award is made in response to a proposal submitted to and reviewed under the NSF/DoE Partnership in Basic Plasma Science and Engineering joint solicitation NSF 08-589. The award provides funds to support travel for a graduate student to scientific conferences and for undergraduate participation in the overall research effort, which is being funded separately by the DoE under contract to UCLA (Science report #09ER55061)This research will use UCLA's unique LAPD facility and its laser plasma capability to do experiments on the coupling of mass, energy, and momentum from a localized, dense, and rapidly expanding plasmas into a large-scale magnetized background plasma. Using the laser we will generate field-aligned plasma flows that can be varied from supersonic to super Alfvénic. The research program is divided into three main topics: 1) the coupling of plasma jets to compressional Alfvén waves, 2) the creation of wakes and structure with supersonic flows, and 3) the interaction of Alfvén waves with fast-flowing plasmas. The experiments will be complemented by computer simulations using a state-of-the-art PIC code developed at UCLA. The code is capable of resolving skin depth structures as well as tracking Alfvénic phenomena. The nonlinear interaction of Alfvén waves with moving plasmas has been the subject of theoretical studies but has never been probed in laboratory experiments. This study is of relevance to phenomena in the Earth's magnetotail, coronal plume expansion within low beta coronal holes, and could be of relevance to astrophysical jets. The NSF support of undergraduate participation adds a broader educational impact through the early-year training of students by introducing them to scientific research as a possible career path.