题目：Laboratory astrophysics with supersonic magnetised plasma flows

报告人：Professor Sergey Lebedev

The Blackett Laboratory, Imperial College, London SW7 2BW, UK

摘要：

In recent years there has been an increasing interest in the modeling of astrophysical phenomena in laboratory experiments using high energy laser and z-pinch facilities, an approach known as High Energy Density Laboratory Astrophysics (HEDLA) [1]. The astrophysical connection in these experiments is provided by appropriate scaling considerations based on dimensionless similarity. The introduction of dynamically significant magnetic fields in HEDLA experiments is a challenging problem: at large magnetic Reynolds numbers (required for scaling), the penetration of an external magnetic field into a plasma is not always possible on the time-scale of an experiment.

The use of plasma flows generated by pulsed power facilities provides a natural platform for designing magnetized HEDLA experiments. The plasma in this case is created and accelerated by the JxB force of the driving, ~Mega-Ampere level currents, forming plasma flows with embedded, frozen-in magnetic fields. In this talk we will review recent experiments performed on the MAGPIE pulsed power facility, focusing on studies of magnetic reconnection in colliding high beta plasmas, and of the structure of magnetized bow-shocks [2,3]. The relatively large spatial and temporal scales characterizing this experimental platform, together with an excellent diagnostic access [4], allow detailed characterization of the key plasma parameters and quantitative comparison of the experimental results with numerical simulations.

简介：

Sergey Lebedev is a professor of Plasma Physics at Imperial College London which he joined in 1996. Prof. Lebedev received his Ph.D. in Physics (1987) from Budker Institute of Nuclear Physics, Novosibirsk, where he worked on the physics of relativistic electron beams and their interaction with plasma. For this work he was awarded the Gold Medal Early Career Award of the Russian Academy of Science (1985). His research at Imperial College, where he leads a group working at the MAGPIE pulsed power facility, covers physics of wire array z-pinches, laboratory astrophysics and plasma diagnostics. He is a Fellow of the American Physical Society (2004) and of the Institute of Physics (2005).

时间：2016年8月29日（星期一）上午9：30  

地点：中科院物理研究所M236会议室

联系人：金奎娟 研究员（Tel：82648099）

邀请人：李玉同研究员  （Tel：82648014）

主办单位：中国科学院光物理重点实验室