[IGPP Everyone] Today: Plasma Science Seminar, Tues. 9/6 2pm, PAB 4-330. "Laboratory studies of reconnection at the magnetopause" (Jongsoo Yoo, Princeton)

[Emmanuel V. Masongsong]

Dear all, 

We have a plasma seminar this Tuesday, September 6th at 2PM in Room 
4-330 of the Physics & Astronomy Building (PAB). Coffee and cookies 
will be available in the room at 1:45. Our speaker is Dr. Jongsoo Yoo 
of the Princeton Plasma Physics Laboratory, and his title and abstract 
are as follows: 

"Laboratory studies of reconnection at the magnetopause" 

Magnetic reconnection at the dayside magnetopause has a large density 
asymmetry across the current sheet due to the inherent difference 
between the solar wind plasma and magnetospheric plasma. To study 
effects of density asymmetry on reconnection, plasmas with a density 
asymmetry up to 10 are created in the Magnetic Reconnection Experiment 
(MRX). The density asymmetry affects the ion flow pattern by changing 
the in-plane electrostatic field such that the potential decrease on the 
high-density side becomes much smaller than that on the low-density side 
[1]. The ion inflow stagnation point is shifted toward the low-density 
side and the maximum ion outflow velocity is observed on the low-density 
side. These features of asymmetric reconnection are consistent with 
numerical simulations and space observations. In addition, we perform 
quantitative analyses on the electron energization and energy inventory 
during asymmetric reconnection and compare the results with the previous 
quasi-symmetric case. The bulk electron heating is proportional to the 
total incoming magnetic energy per particle. How electrons are energized 
during asymmetric reconnection is discussed. Finally, the scaling of the 
reconnection rate and the ion outflow speed given by the Cassak and Shay 
2007 [2] is tested by systematically varying the density ratio across 
the current sheet. The measured ion outflow speed is about 40% of the 
theoretical values and the measured reconnection rate agrees with the 
scaling only with the measured density in the exhaust region. 

[1] J. Yoo et al., Phys. Rev. Lett. 113, 095002 (2014). 
[2] P. Cassak and M. Shay, Phys. Plasmas 14, 102114 (2007). 

http://www.pa.ucla.edu/sites/default/files/plasma_Yoo9616.pdf