Sunspot transition region oscillations
Abstract
Intensity and velocity oscillations have been observed over a period of 4.3 hours in lines of Ne VIII and C IV with the SUMER spectrograph aboard SOHO. These lines are formed in the EUV plume above a sunspot. Applying a wavelet analysis, we find oscillations mainly close to 3 mHz. The temporal behaviour is strongly intermittent, particularly for the velocity oscillations. This non-stationary behaviour may be related with occurrence of blinkers in the umbral transition region.
- Publication:
-
SOHO 10/GONG 2000 Workshop: Helio- and Asteroseismology at the Dawn of the Millennium
- Pub Date:
- January 2001
- Bibcode:
- 2001ESASP.464..235R
- Keywords:
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- SUN;
- SOLAR OSCILLATIONS;
- UV SPECTRA