From the Observation of Non-symmetrical Profiles of the C IV Resonance Lines for Small Dynamic Events to their Interpretation in Terms of Resonant Scattering in Solar Active Regions
Abstract
We present observations of small areas in solar active regions recorded with the SUMER/SOHO spectrograph where the C IV 1548A and 1550A lines have spectral profiles of different shapes, although they are recorded simultaneously and at the same location. We propose to explain this asymmetry by resonant scattering of strong incident radiation from close-by regions, associated with relative velocities of the emitting plasmas. We present detailed artificial spectral profiles that may explain the observations. The profiles have been computed using several physical parameters such as the plasma temperature and electron density and the incident radiation on the emitting volumes. We conclude that the study of asymmetries in the C IV 1548A, 1550A lines, and also in different doublets (e.g. Si IV for IRIS), should include this radiative interaction and moreover that it can be a valuable diagnostic tool for deriving the physical conditions in solar/stellar plasmas, especially where the radiation processes (such as flare-emission) are enhanced at the vicinity of the observed structures.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMSH33A..01V
- Keywords:
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- 7599 General or miscellaneous;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMYDE: 7899 General or miscellaneous;
- SPACE PLASMA PHYSICSDE: 7999 General or miscellaneous;
- SPACE WEATHER