Abstract
Jet-like eruptive events have been detected in the extreme ultraviolet (EUV) observations from the Solar and Heliospheric Observatory (SOHO) spacecraft. Some jet-like events are shown and for one event, that of January 22 2000, we provide a detailed analysis of the EUV observations. The January 22 observation was part of an on-going campaign to observe the onset of coronal mass ejections (CMEs) using extreme ultraviolet spectroscopy. A high-temperature fan-like jet was first detected in emission lines from plasmas at one million K and over, and it appears to be the onset of a narrow mass ejection identified later in coronagraph data. This was followed by a dramatic jet or finger of cool ($\le$250 000 K), rotating plasma which extended vertically, high into the corona. It extended well beyond the field of view of the instrument and appears to relate to a small ejected cloud which is detected in subsequent coronagraph data. The spectroscopic characteristics are used to provide plasma diagnostic information for these two events, and this combined with images for a wide range of temperatures allows a thorough investigation of the processes leading to such eruptions. A simple accreting magnetic field model is used to descibe the basic features of the jet activity.
Original language | English |
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Pages (from-to) | 324-335 |
Number of pages | 12 |
Journal | Astronomy and Astrophysics |
Volume | 379 |
Issue number | 1 |
DOIs | |
Publication status | Published - 3 Nov 2001 |
Keywords
- UV radiation
- solar corona
- solar atmosphere
- sun