Structure of the magnetopause for low Mach number and strongly northward interplanetary magnetic field

Journal Article · Thu Dec 01 04:00:00 EST 1994 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/94JA02182· OSTI ID:91344

Le, G; Russell, C T ^[1]; Gosling, J T ^[2]

---

1. Univ. of California, Los Angeles, CA (United States)
2. Los Alamos National Lab., NM (United States)

The authors use ISEE magnetic field and plasma data to examine dayside magnetopause crossings under conditions of low Mach number and strongly northward interplanetary magnetic field (IMF). When the solar wind Mach number is low, the IMF strength and magnetosheath field strength are large, and they expect the effects of magnetic reconnection to be the strongest. When the IMF is strongly northward, they find that the location of the magnetopause boundary layer is very stationary in the space, and they observe many features that are common for both typical and low Mach numbers. However, under low Mach number conditions, the authors have observed some features that would be expected for cusp reconnection. The boundary layer near the subsolar region contains heated magnetosheath plasma with little hot magnetospheric component that has clearly entered the magnetosphere elsewhere. At least some of the structures present in the boundary layer are impulsive. Inside the boundary layer there is also clear evidence of accelerated flow from the cusp region for strongly northward IMF at low Mach number. Therefore at low Mach number, reconnection is important in the formation of the boundary layer for northward IMF.

• OSTI ID: 91344
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: A12 Vol. 99; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
INTERPLANETARY MAGNETIC FIELDS
MACH NUMBER
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOPAUSE
SOLAR WIND
STABILITY