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Title: DIRECT OBSERVATIONAL EVIDENCE OF FILAMENT MATERIAL WITHIN INTERPLANETARY CORONAL MASS EJECTIONS

Journal Article · · Astrophysical Journal Letters

Coronal mass ejections (CMEs) are explosive events that escape the Sun's corona carrying solar material and energy into the heliosphere. The classic picture of a CME observed in the corona presents a 'three-part structure', including a bright front at the leading edge indicating dense plasma, a low-density cavity, the possible signature of an embedded magnetic flux rope, and the so-called core, a high-density region observed to be associated with an erupting filament. Although there are experimental analogs to the first two parts of the CME when observed in situ, there are only a handful of in situ observations of cold, filament-type plasma. This has been a source of major uncertainty and qualitative disagreement between remote and in situ observations of these ejecta. We present the first comprehensive and long-term survey of such low charge states observed by the Advanced Composition Explorer Solar Wind Ion Composition Spectrometer, using a novel data analysis process developed to identify ions with low ionic charge states. Using a very stringent set of observational signatures, we find that more than 4% of detected interplanetary CMEs have significant contributions of ions with low charge states. These time periods of low-charge ions often occur concurrent with some of the hottest ions, previously interpreted to be affected by flare heating during the CME initiation.

OSTI ID:
21452722
Journal Information:
Astrophysical Journal Letters, Vol. 723, Issue 1; Other Information: DOI: 10.1088/2041-8205/723/1/L22; ISSN 2041-8205
Country of Publication:
United States
Language:
English