NJIT Physics Department Seminar

January 30th, Monday, 2017

Magnetic Reconnection in Space and Laboratory Plasmas

Prof. C. Z. “Frank” Cheng

Institute of Space and Plasma Sciences

National Cheng Kung University, Taiwan

(Solar Physics, Host: Gary)

Time: 11:45am-12:45pm with 11:30am tea time

Room: ECE 202

Magnetic reconnection is a key physical mechanism of converting magnetic energy into plasma energy. In solar and stellar flares, magnetic reconnection plays the essential role of accelerating electrons to MeV energy and ions to GeV energy. In the planetary magnetospheres, magnetic reconnection plays the critical role of solar-wind magnetosphere interaction so that solar wind particles can enter magnetosphere and be stored in the plasma sheet. In laboratory magnetic confinement fusion plasmas, magnetic reconnection is the mechanism of causing plasma disruption in tokamaks. It has also been used to convert magnetic energy into plasma energy to startup plasmas with high ion temperature in the fusion reactor plasma regime. In this talk I will first review the historical development of magnetic reconnection theories/simulations. Then, I will present the kinetic physics of magnetic reconnection and show how and where electrons and ions are accelerated/heated. I will also present the electron and ion heating results obtained in the laboratory magnetic reconnection experiments. Then, I will present the magnetic reconnection process in solar flares and coronal mass ejections phenomena. In particular, I will discuss how the kinetic theory of magnetic reconnection can help resolve the “electron number problem” in the solar flares.

Short Bio of Prof. C. Z. (Frank) Cheng:

Prof. C. Z. (Frank) Cheng received a PhD degree in physics from University of Iowa in 1975. Then, he worked at Prince Plasma Physics Laboratory (PPPL), Princeton University for 30 years (1975-2005), and was a Distinguished Research Fellow when he retired in 2005. Then, he joined National Space Organization (NSPO), Taiwan during 2005-2007 as its Chief Scientist. In 2006 he moved to National Cheng University (NCKU), Taiwan as a Chair Professor and established Plasma and Space Science Center (PSSC) and then established the Institute of Space and Plasma Sciences (ISAPS) in 2008. He is now an MOST Chair at NCKU for one year (2016-2017). Prof. Cheng’s research is mainly in theory and simulation of plasma physics with applications in fusion plasmas, basic laboratory plasmas, and space plasmas. Prof. Cheng is an APS fellow since 1991 and a Fellow of Physical Society of Republic of China (Taiwan) since 2009. He received the “Award For Excellence In Plasma Physics Research” by American Physical Society in 2004. In 2013 he also received the “John Dawson Prize for Numerical Simulation of Plasmas” by the International Conference on Numerical Simulation of Plasmas.