Dual-line analysis of sunspot oscillations
Abstract
Umbral oscillations and running penumbral (RP) waves are studied with simultaneous, two-dimensional, high cadence (8 sec), dual-line sunspot observations in Ca II 8542 Å and Halpha , obtained with the MSDP spectrograph on the German VTT in Tenerife. Doppler velocity and intensity images are used to investigate the physical characteristics of umbral flashes (UFs) and RP waves while a wavelet spectral and phase analysis shows their temporal behaviour and permits us to elaborate on their nature and possible association.
- Publication:
-
Memorie della Societa Astronomica Italiana
- Pub Date:
- 2007
- Bibcode:
- 2007MmSAI..78...98T
- Keywords:
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- Sun: chromosphere;
- Sun: oscillations;
- Sun: sunspots