Large-scale Interstellar Structure and the Heliosphere

P. C. Frisch; N. A. Schwadron

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arXiv · 1310.2922

Large-scale Interstellar Structure and the Heliosphere

P. C. Frisch·N. A. Schwadron

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Abstract

The properties of interstellar clouds near the Sun are ordered by the Loop I superbubble and by the interstellar radiation field. Comparisons of the kinematics and magnetic field of the interstellar gas flowing past the Sun, including the Local Interstellar Cloud (LIC), indicate a geometric relation between Loop I as defined by radio synchrotron emission, and the interstellar magnetic field that polarizes nearby starlight. Depletion of Fe and Mg onto dust grains in the LIC shows a surprising relation to the far ultraviolet interstellar radiation field that is best explained by a scenario for the LIC to be extended, possibly filamentary, porous material drifting through space with the Loop I superbubble. The interstellar velocity and magnetic field measured by the Interstellar Boundary Explorer (IBEX) help anchor our understanding of the physical properties of the nearby interstellar medium.

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P. C. Frisch, N. A. Schwadron. 2013-10-10. Large-scale Interstellar Structure and the Heliosphere. https://arxiv.org/abs/1310.2922

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