The plasmaspheric plume and magnetopause reconnection

Abstract

We present near‐simultaneous measurements from two THEMIS spacecraft at the dayside magnetopause with a 1.5 h separation in local time. One spacecraft observes a high‐density plasmaspheric plume while the other does not. Both spacecraft observe signatures of magnetic reconnection, providing a test for the changes to reconnection in local time along the magnetopause as well as the impact of high densities on the reconnection process. When the plume is present and the magnetospheric density exceeds that in the magnetosheath, the reconnection jet velocity decreases, the density within the jet increases, and the location of the faster jet is primarily on field lines with magnetosheath orientation. Slower jet velocities indicate that reconnection is occurring less efficiently. In the localized region where the plume contacts the magnetopause, the high‐density plume may impede the solar wind‐magnetosphere coupling by mass loading the reconnection site.

Particle-in-cell simulation study of the scaling of asymmetric magnetic reconnection with in-plane flow shear

“…It is not clear whether this is physical or only a function of the finite system size in the simulations, so it is worth future study. We point out that a limit with such strong flows is not likely to apply at the magnetosphere except possibly when the reconnection site interacts with the dense, cold plasmas in plasmaspheric drainage plumes [41][42][43] , but may be important in tokamaks.…”

Cold ion heating at the dayside magnetopause during magnetic reconnection

“…One noticeable change in reconnection when a significant amount of cold ions is present is the reduction of the reconnection rate and the Alfvén velocity due to the system mass loading [Walsh et al, 2014]. In addition, cold ions have a smaller gyroradius than hot ions and introduce a new length-scale Toledo-Redondo et al, 2015].…”

“…Some studies have accounted for cold ions in the reconnection process, e.g., Su et al [2000], McFadden et al [2008], André et al [2010], Walsh et al [2014], , Wang et al [2014], Wang et al [2015], and Toledo-Redondo et al [2015]. Some studies have accounted for cold ions in the reconnection process, e.g., Su et al [2000], McFadden et al [2008], André et al [2010], Walsh et al [2014], , Wang et al [2014], Wang et al [2015], and Toledo-Redondo et al [2015].…”

The story of plumes: the development of a new conceptual framework for understanding magnetosphere and ionosphere coupling

“…This paper will first briefly describe each of the different plumes independently (starting from the largest scale and moving to smallest scale and from the magnetosphere to the ionosphere) and then will synthesize the literature that has led to a new understanding of magnetosphere-ionosphere (MI) coupling. What is now clear is that plumes connect the equatorial F region ionosphere to the dayside magnetopause and the nightside magnetotail plasma sheet (e.g., Su et al, 2001a, b;Horvath and Lovell, 2011;Walsh et al, 2014a, b;Foster et al, 2014). Through the formation and evolution of the different plumes, they impact wave generation and wave-particle interactions (e.g., Summers et al, 2008;Chen et al, 2012;Halford et al, 2015), particle precipitation (Spasojević and Fuselier, 2009;Yuan et al, 2011Yuan et al, , 2013, ion outflow (e.g., Zeng and Horowitz, 2008;Tu et al, 2007), local-time asymmetries in ULF wave field-line resonance (FLR) signatures (e.g., Archer et al, 2015;Ellington et al, 2016), satellite communication and navigation systems (Ledvina et al, 2004;Basu et al, 2005;Datta-Barua et al, 2014), and even the coupling efficiency of the solar wind to the magnetosphere (Borovsky and Denton, 2006;Borovsky et al, 2013;Ouellette et al, 2016;Fuselier et al, 2016).…”