SPACE AND COSMIC RAY PHYSICS SEMINAR

University of Maryland
Atlantic Building, Room 2400 4:30 PM Monday, February 2, 2009
Coffee, Tea & Snacks 4:15-4:30 PM

Dr. Marc Swisdak
University of Maryland

Magnetic Reconnection in the Solar Wind and at the Heliopause

I will discuss recent work bringing together numerical simulations of magnetic reconnection and observations in the near-Earth solar wind and the outer heliosphere. In the solar wind, observations suggest that ions can be heated when they encounter the outflow from a magnetic x-line. Simulations suggest that this happens when the ions are effectively "picked-up" by the exhaust, a process that leads to a temperature increment proportional to the ion mass. Second, after crossing the termination shock, Voyager 2 observations indicated that pickup ions account for most of the downstream energy, and hence that that the plasma beta is significantly larger than unity. Simulations indicate that this will lead to magnetic reconnection being stabilized over most of the heliopause, a claim that may be tested by future Voyager data.