 |
| Titel |
Signatures of interplanetary transients behind shocks and their associated near-surface solar activity |
| VerfasserIn |
S. Bravo, X. Blanco-Cano |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 16, no. 4 ; Nr. 16, no. 4, S.359-369 |
| Datensatznummer |
250013237
|
| Publikation (Nr.) |
 copernicus.org/angeo-16-359-1998.pdf |
|
|
|
|
|
| Zusammenfassung |
Interplanetary transients with particular
signatures different from the normal solar wind have been observed behind
interplanetary shocks and also without shocks. In this paper we have selected
four well-known transient interplanetary signatures, namely: magnetic clouds,
helium enhancements and bidirectional electron and ion fluxes, found in the
solar wind behind shocks, and undertaken a correlative study between them and
the corresponding solar observations. We found that although commonly different
signatures appear in a single interplanetary transient event, they are not
necessarily simultaneous, that is, they may belong to different plasma regions
within the ejecta, which suggests that they may be generated by complex
processes involving the ejection of plasma from different solar regions. We also
found that more than 90% of these signatures correspond to cases when an
Hα flare and/or the eruption of a filament occurred near solar
central meridian between 1 and 4 days before the observation of the disturbance
at 1 AU, the highest association being with flares taking place between 2 and 3
days before. The majority of the Hα flares were also accompanied by
soft X-ray events. We also studied the longitudinal distribution of the
associated solar events and found that between 80% and 90% of the interplanetary
ejecta were associated with solar events within a longitudinal band of ±30°
from the solar central meridian. An east-west asymmetry in the associated solar
events seems to exist for some of the signatures. We also look for coronal holes
adjacent to the site of the explosive event and find that they were present
almost in every case.
Key words. Interplanetary physics · Interplanetary
shocks · Solar wind plasma · Solar physics · Flares and mass ejections |
| |
|
| Teil von |
|
|
|
|
|
|
|
|