The ribbon might indicate the region of highest pressure and density in the heliosheath where the outward flow of solar wind particles would greatly slow down, and where energetic neutral atoms (ENAs) would be created in greater numbers as the particles bunch together. The pressure might also push out small regions of the heliopause, forming bulges of very high density, potentially explaining the observed fine structures in the ribbon.
' }); $("#ribbonexp2").qtip({ show: "mouseover", hide: { when: "mouseout", fixed: true }, position: { corner: { target: "topMiddle", tooltip: "bottomMiddle" }}, style: { width: 300, padding: 10, border: { width: 5, radius: 5}}, content: 'Primary ENAs from CompressionGreater numbers of ENAs may be produced where the local galactic magnetic field lines could be more highly compressed. These ENAs would be coming from a region outside of the heliopause. When ions are compressed with the galactic magnetic field, they become aligned more closely perpendicular to the galactic magnetic field. This leads to greater numbers of ENAs that come from a ring similar to the IBEX Ribbon, as shown in an article by IBEX team members Dr. Nathan Schwadron, et al, in October 2009.
' }); $("#ribbonexp3").qtip({ show: "mouseover", hide: { when: "mouseout", fixed: true }, position: { corner: { target: "topMiddle", tooltip: "bottomMiddle" }}, style: { width: 300, padding: 10, border: { width: 5, radius: 5}}, content: 'Secondary ENAsIn this model, a first batch of ENAs is created inside the heliosheath. As these ENAs travel outward past the heliopause, they exchange charge with other ions. Those ENAs would then themselves become ions as they rotate approximately perpendicular to the galactic magnetic field along a ring similar to the IBEX Ribbon. When these ions charge-exchange again with interstellar hydrogen, they become new “secondary” ENAs. These secondary ENAs could travel backwards toward the inner solar system and be captured by IBEX. For more information about this model, check out a recent Science@NASA article and an Astrophysical Letters article by IBEX team members Dr. Jacob Heerikhuisen, et al, in January 2010.
' }); $("#ribbonexp4").qtip({ show: "mouseover", hide: { when: "mouseout", fixed: true }, position: { corner: { target: "topMiddle", tooltip: "bottomMiddle" }}, style: { width: 300, padding: 10, border: { width: 5, radius: 5}}, content: 'ENAs from Magnetic ReconnectionThe external pressure of the local galactic magnetic field on our heliosphere is greatest in the direction perpendicular to the magnetic field. This pressure could enhance the rate of magnetic reconnection where different magnetic field lines would splice together, causing greater numbers of ENAs to be created in these areas.
' }); $("#ribbonexp5").qtip({ show: "mouseover", hide: { when: "mouseout", fixed: true }, position: { corner: { target: "topMiddle", tooltip: "bottomMiddle" }}, style: { width: 300, padding: 10, border: { width: 5, radius: 5}}, content: 'ENAs from Shock-Accelerated Pickup IonsAnother possible idea is that the IBEX Ribbon ENAs might somehow be coming from inside but near the termination shock, perhaps from ions that are accelerated at the termination shock.
' }); $("#ribbonexp6").qtip({ show: "mouseover", hide: { when: "mouseout", fixed: true }, position: { corner: { target: "topMiddle", tooltip: "bottomMiddle" }}, style: { width: 300, padding: 10, border: { width: 5, radius: 5}}, content: 'ENAs from Heliopause InstabilitiesWave-like unstable regions in the outer edge of the heliosphere may confine the hot heliosheath plasma in narrow areas. ENAs may be produced in these areas in greater numbers.
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