IBEX OBSERVATIONS OF SECONDARY INTERSTELLAR HELIUM AND OXYGEN DISTRIBUTIONS
- Space Science Center and Department of Physics, University of New Hampshire, 8 College Road, Durham, NH 03824 (United States)
- Physics Institute, University of Bern, Bern 3012 (Switzerland)
- Space Research Centre of the Polish Academy of Science, Warsaw (Poland)
In this study, we investigate the directional distributions of the secondary interstellar neutral (ISN) He and O populations at Earth's orbit. The secondary populations are created by charge exchange between ISN atoms and interstellar ions in the outer heliosheath. Using the IBEX -Lo He and O observations during the winter–spring seasons (early December to early June) in 2009–2011, we produced all-sky maps for He and O atoms with sputtering corrections. These sky maps include the directional distributions of the primary ISN gas and secondary populations. Our investigations reveal that the secondary He and O populations are observed in the ecliptic longitude range 160°–210°. The peak longitudes of the secondary He and O appear to be 14°–34° and 38°–43° away from the peak longitude of the primary interstellar gas flow, respectively. These results indicate that the secondary populations have lower bulk speeds relative to the Sun and their flow directions deviate from the primary gas flow. These results may indicate that one side of the outer heliosheath is thicker than the other side relative to the flow direction of the primary interstellar gas flow.
- OSTI ID:
- 22660900
- Journal Information:
- Astrophysical Journal, Vol. 833, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
INTERSTELLAR NEUTRAL HELIUM IN THE HELIOSPHERE FROM IBEX OBSERVATIONS. IV. FLOW VECTOR, MACH NUMBER, AND ABUNDANCE OF THE WARM BREEZE
Determination of interstellar He parameters using five years of data from the IBEX: Beyond closed form approximations