A movie of small-scale Doppler velocities in a quiescent prominence
Abstract
A movie made of selected H off-band images of a typical Quiescent Prominences has been produced with the optical printer of NSO-S.P. High speed pictures were obtained with the UBF of the VTT on June 21, 1987 during 30 min of very good seeing, at a 20 sec cycling rate. Blue and red wings images are made at plus and minus .040 nm from line center, with a .022 nm passband. Original Pictures were enlarged to give an effective field of view of 100 × 80 arcsec2. Negative to positive superposition allows the mapping of strongly Doppler-shifted features (± 20 km sec-1) on a grey scale. The prominence threads are mostly discrete, allowing accurate measurement of proper motions. Typical transverse velocities of proper motions of small knots moving vertically downward are about 10 km sec-1 The movie also demonstrates the turbulent behaviour of the prominence plasma. Large-scale motions at lower transverse velocities are also clearly present.
- Publication:
-
IAU Colloq. 117: Dynamics of Quiescent Prominences
- Pub Date:
- 1990
- DOI:
- 10.1007/BFb0025659
- Bibcode:
- 1990LNP...363..240K