Retreat and reformation of X-line during quasi-continuous tailward-of-the-cusp reconnection under northward IMF

• We present observations on 19-20 November 2006 by the Cluster spacecraft that were skimming the high-latitude dusk-flank magnetopause, which are consistent with more than one reconnection X-line present on the tailward side of the cusp under northward IMF. Evidence of quasi-continuous reconnection over 16 hours exists in the form of Alfvenic acceleration of magnetosheath ions found almost always when either of the satellites traversed the boundary. The data indicate that a dominant X-line was sunward of Cluster for most of the time, but ion velocity distributions consisting of two magnetosheath populations demonstrate that for part of the time, more than one X-line existed. Further, the motion of reconnected field lines shows that some X-line(s) retreated tailward. It is inferred that following the X-line retreat, another X-line reformed sunward of Cluster, leading tomultiple X-lines.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

Physics

Fysik

Publication and Content Type

ref (subject category)

art (subject category)