SH53C-04
Properties of ENA Source Regions Outside the Heliopause
Friday, 18 December 2015: 14:16
2011 (Moscone West)
Jacob Heerikhuisen1, Eric Zirnstein2, Konstantin V Gamayunov3, Nikolai Pogorelov1, Herbert O Funsten4, Vladimir A Florinski5 and Annaleah E Ernst6, (1)University of Alabama in Huntsville, Space Science, Huntsville, AL, United States, (2)Southwest Research Institute, San Antonio, TX, United States, (3)Florida Institute of Technology, Department of Physics, Melbourne, FL, United States, (4)Los Alamos Natl Laboratory, Los Alamos, NM, United States, (5)University of Alabama in Huntsville, Huntsville, AL, United States, (6)Harvard University, Cambridge, MA, United States
Abstract:
While no definitive sequence of physical processes has been identified as the underlying cause of the ribbon of enhanced ENA flux observed by IBEX, models based on the so-called "secondary ENA" mechanism appear best able to reproduce the observed ribbon features. The secondary ENA mechanism involves primary ENAs exiting the heliosphere, giving rise to a population of energetic pick-up ions in the outer heliosheath region within a few hundred AU of the heliopause. Several possible scattering scenarios for these pick-up ions then result in a preferential ENA signal from regions where the interstellar magnetic field is close to perpendicular to the line of sight. We will present results from our simulations of the global heliosphere that include a kinetic description of neutral hydrogen. The properties of the source population for outer heliosheath pick-up ions will be shown, along with details of the magnetic field that drapes over the heliopause. A brief overview of the ribbon properties predicted by our model, and some new results for the pick-up ion scattering process will also be presented.
