SSP seminar

Insight on the IBEX-Hi Energetic Neutral Atoms Maps

Christina Prested (Boston University)

Monday 19th July 2010, 12:00pm
Pratt conference room, 60 Garden Street

Energetic neutral atom (ENA) imaging is a relatively new technique to remotely view warm plasmas. First developed to view magnetospheres, it is now applied to the outer boundaries of the solar system, where the solar wind and the interstellar medium collide. In 2009 the Interstellar Boundary Explorer (IBEX) completed its first all-sky ENA maps of the solar system boundaries. The maps are characterized by a power-law energy distribution and an unexpected Ribbon like feature of strong emission.

I will present magnetohydrodynamic simulations of ENA maps based on the pre-IBEX understanding of the heliosphere and discuss how the IBEX results affect that understanding. Particularly, I concentrate on results from the IBEX-Hi sensor which detects ENAs in 6 energy channels that cover 0.2 and 6 keV, a range dominated by pick-up ions with characteristic energy of ~ 1 keV. I describe a new method for connecting the ENA measurements to the parent plasma, and use this method to explain the observed IBEX power-law energy distribution. In the conclusion of the talk, I test this method using the observations from Voyager 2 in the heliosheath and compare to the IBEX-Hi measurements.


Section Photo