Seven Years of Imaging the Global Heliosphere with IBEX

Abstract

The Interstellar Boundary Explorer (IBEX) has now operated in space for 7 years and returned nearly continuous observations that have led to scientific discoveries and reshaped our entire understanding of the outer heliosphere and its interaction with the local interstellar medium. Here we extend prior work, adding the 2014-2015 data for the first time, and examine, validate, initially analyze, and provide a complete 7-year set of Energetic Neutral Atom (ENA) observations from ~0.1 to 6 keV. The data, maps, and documentation provided here represent the 10th major release of IBEX data and include improvements to various prior corrections to provide the citable reference for the current version of IBEX data. We are now able to study time variations in the outer heliosphere and interstellar interaction over more than half a solar cycle. We find that the Ribbon has evolved differently than the globally distributed flux (GDF), with a leveling off and partial recovery of ENAs from the GDF, owing to solar wind output flattening and recovery. The Ribbon has now also lost its latitudinal ordering, which reflects the breakdown of solar minimum solar wind conditions and exhibits a greater time delay than for the surrounding GDF. Together, the IBEX observations strongly support a secondary ENA source for the Ribbon, and we suggest that this be adopted as the nominal explanation of the Ribbon going forward.

Pre-print, 59 pages, 33 figures, published in ApJS

References in corpus (18)

• Scatter-free pickup ions beyond the heliopause as a model for the Interstellar Boundary Explorer (IBEX) ribbon
• Heliolatitude and time variations of solar wind structure from in situ measurements and interplanetary scintillation observations
• Interstellar neutral helium in the heliosphere from IBEX observations. III. Mach number of the flow, velocity vector, and temperature from the first six years of measurements
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• Local Interstellar Neutral Hydrogen sampled in-situ by IBEX
• The Solar Wind Energy Flux
• Spatial Confinement of the IBEX Ribbon: A Dominant Turbulence Mechanism
• Reconstruction of Helio-latitudinal Structure of the Solar Wind Proton Speed and Density
• Neutral interstellar hydrogen in the inner heliosphere under the influence of wavelength-dependent solar radiation pressure
• Local Interstellar Hydrogen's Disappearance at 1 Au: Four Years of IBEX in the Rising Solar Cycle
• Distance to the IBEX Ribbon Source Inferred from Parallax
• Interstellar hydrogen fluxes measured by IBEX-Lo in 2009: numerical modeling and comparison with the data
• The energy-dependent position of the IBEX ribbon due to the solar wind structure
• Evidence for an interstellar dust filament in the outer heliosheath

Cited by in corpus (20)

• Three-dimensional Features of the Outer Heliosphere Due to Coupling between the Interstellar and Heliospheric Magnetic Field. V. The Bow Wave, Heliospheric Boundary Layer, Instabilities, and Magnetic Reconnection
• Interstellar Pickup Ion Observations to 38 AU
• Sun-Heliosphere Observation-based Ionization Rates Model
• In Situ Observations of Preferential Pickup Ion Heating at an Interplanetary Shock
• Plasma pressures in the heliosheath from Cassini ENA and Voyager 2 measurements: Validation by the Voyager 2 heliopause crossing
• Evolution of the Solar Lyman-Alpha line profile during the solar cycle
• Interstellar neutral helium in the heliosphere from IBEX observations. V. Observations in IBEX-Lo ESA steps 1, 2, & 3
• The downwind hemisphere of the heliosphere: Eight years of IBEX-Lo observations
• A new 3D solar wind speed and density model based on interplanetary scintillation
• Evolution of the solar Ly-$\alpha$ line profile during the solar cycle. II. How accurate is the present radiation pressure paradigm for interstellar neutral H in the heliosphere?
• Heliosheath Properties Measured from a Voyager 2 to Voyager 1 Transient
• Solar wind energy flux observations in the inner heliosphere: First results from Parker Solar Probe
• Thermodynamics of the inner heliosheath
• Interstellar Now! Missions to and Sample Returns from Nearby Interstellar Objects
• Investigating the IBEX Ribbon Structure a Solar Cycle Apart
• Modeling Emission of Heavy Energetic Neutral Atoms from the Heliosphere
• An empirical model of Energetic Neutral Atom imaging of the heliosphere and its implications for future heliospheric missions at great heliocentric distances
• Spherical Harmonic Representation of Energetic Neutral Atom Flux Components Observed by IBEX
• Production and Loss Processes of Hydrogen Energetic Neutral Atoms in the Heliosphere from 5 eV to 500 keV
• Variations in the pickup ion density structure in response to the growth of the Kelvin--Helmholtz instability along the heliopause