March 2, 2018, 1:00 pm - 2:00 pm

March 2, 1:00 pm - 2:00 pm

The Dynamics of the S-Web and Implications for Heliospheric Particle Distributions

A. K. Higginson(1), S. K. Antiochos(2), C. R. DeVore(2), B. J. Lynch(3), P. F. Wyper(4), T. H. Zurbuchen(5)

1 CLASP, University of Michigan, Ann Arbor, MI

2 NASA Goddard Space Flight Center, Greenbelt, MD

3 Space Sciences Laboratory, University of California, Berkeley, CA

4 Dept. Mathematical Sciences, Durham University, Durham, UK

5 NASA Headquarters, Washington, D.C.

Particle transport in the heliosphere remains an unsolved problem across energy regimes. Two mysteries posed by in-situ observations are 1) the large latitudinal extent of slow solar wind about the heliospheric current sheet (HCS) and 2) the large longitudinal spread (over 100 degrees) of some impulsive solar energetic particle (SEP) events. In the classical picture of the solar/heliospheric magnetic field, slow solar wind should occur only near the HCS and impulsive SEPs should occupy only a narrow spread about the point of origin in the corona. The recently proposed Separatrix-Web (S-Web) Theory postulates that these observations can be explained by the dynamic interaction of open and closed flux in regions of complex coronal-hole topology that can establish magnetic-field connections ranging far in latitude and longitude. This is a promising mechanism for explaining both the slow solar wind, with its large latitudinal extent, and impulsive SEP particles, with their large longitudinal extent. I will present the first numerical simulations of the dynamic S-Web and discuss its effects on the slow solar wind and impulsive SEP populations. These simulations suggest that photospheric motions at coronal-hole boundaries are responsible for the release of slow solar wind plasma from the magnetically closed solar corona, specifically through prolific interchange magnetic reconnection. I will also show how energetic particles that are accelerated within a small region on the Sun near a coronal-hole corridor could be observed many tens of degrees in longitude away from the flare region in the heliosphere as a result of these background dynamics. These results show that understanding the complex mapping of the magnetic field from the Sun to the heliosphere, and the dynamics of that mapping, is essential for understanding the observed properties of interplanetary plasma and particles. I will make predictions for Solar Orbiter and Parker Solar Probe and discuss how these new measurements will help to both pinpoint the source of the slow solar wind and illuminate the transport mechanisms of wide-spread impulsive SEP events.