The fine structure of prominences
β Scribed by O. Engvold; J. McKim Malville
- Publisher
- Springer
- Year
- 1977
- Tongue
- English
- Weight
- 354 KB
- Volume
- 52
- Category
- Article
- ISSN
- 0038-0938
No coin nor oath required. For personal study only.
β¦ Synopsis
Faint, Doppler shifted, emission features are detected in high resolution spectra of limb prominences. Their average line-of-sight velocity is about 3 x 106 cm s i, their average life time is 300 s, and their angular sizes are ~<10 s cm in our spectrograms. The emission line width of the spectral features increases with increasing line shift.
Some implications on the stability of prominences by these structures are discussed briefly.
π SIMILAR VOLUMES
A model of a quiescent prominence with nonparallel structural elements, based on a study of the K Ca Β§ line fine structure of two quiescent prominences. The dependences of the radial velocities on the height found for the structural elements making up the prominence (Gigolashvili and Zhugzhda, 1982)
The vertical fine structure in a quiescent prominence was modelled as an assembly of very narrow, optically thin threads. Random clusterings of the threads can account for the observed contrast and He line profiles of the fine structures. In this picture, each structure consists of a cluster of 7-20
Observed Ha brightness versus size of emission substructures of quiescent prominences are compared with values predicted from thermodynamical models. The measured size of an emission element of a given brightness is substantially less than the theoretical value. Two possible causes for the discrepa
A random-clustering model of prominence fine-structure has been applied to observations of prominence Ha spectra. The model yields an estimate of the number of unresolved elements that form an individual resolved feature, and sets limits on their velocity and Ha profile dispersions.