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| Titel |
Long-Term Tracking of Corotating Density Structures Using Heliospheric Imaging (catalogue of CIRs during 2007-2014) |
| VerfasserIn |
Illya Plotnikov, Alexis P. Rouillard, Jackie Davies, Volker Botmer, Jonathan Eastwood, Peter Gallagher, Richard Harrison, Emilia Kilpua, Christian C. Möstl, Chris Perry, Luciano Rodriguez, Benoit Lavraud, Vincent Génot, Rui Pinto, Eduardo Sanchez-Diaz |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250141025
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| Publikation (Nr.) |
 EGU/EGU2017-4486.pdf |
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| Zusammenfassung |
| The systematic monitoring of the solar wind in high-cadence and high-resolution heliospheric
images taken by the Solar-Terrestrial Relation Observatory (STEREO) spacecraft permits the
study of the spatial and temporal evolution of variable solar wind flows from the Sun out to
1 AU, and beyond. As part of the EU Framework 7 (FP7) Heliospheric Cataloguing,
Analysis and Techniques Service (HELCATS) project, we have generated a catalogue listing
the properties of more than 190 corotating structures well-observed in images taken by the
Heliospheric Imager (HI) instruments on-board STEREO-A (ST-A). Based on
this catalogue, we present here one of very few long-term analyses of solar wind
structures advected by the background solar wind. We concentrate on the subset
of plasma density structures clearly identified inside corotating structures. This
analysis confirms that most of the corotating density structures detected by the
heliospheric imagers comprises a series of density inhomogeneities advected by the slow
solar wind that eventually become entrained by stream interaction regions. We have
derived the spatial-temporal evolution of each of these corotating density structures
by using a well-established fitting technique. The mean radial propagation speed
of the corotating structures is found to be 311 ± 31 km s−1. We show that the
speeds of the corotating density structures derived using our fitting technique track
well the long-term variation of the radial speed of the slow solar wind during solar
minimum years (2007–2008). Furthermore, we demonstrate that these features
originate near the coronal neutral line that eventually becomes the heliospheric current
sheet. |
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