Rotating transition region features observed with the SOHO coronal diagnostic spectrometer

Citation
Cd. Pike et He. Mason, Rotating transition region features observed with the SOHO coronal diagnostic spectrometer, SOLAR PHYS, 182(2), 1998, pp. 333-348
Citations number
27
Categorie Soggetti
Space Sciences
Journal title
SOLAR PHYSICS
ISSN journal
00380938 → ACNP
Volume
182
Issue
2
Year of publication
1998
Pages
333 - 348
Database
ISI
SICI code
0038-0938(199810)182:2<333:RTRFOW>2.0.ZU;2-3
Abstract
Strong evidence has been found from SOHO-CDS (Solar and Heliospheric Observ atory - Coronal Diagnostic Spectrometer) observations to support the hypoth esis that rotation plays a major role in the dynamics of transition region features. A comprehensive survey of the CDS daily synoptic rasters has been carried out to select dynamic events by searching for spectral line shifts in the O V emission line at 629.73 Angstrom (formed at a temperature of 2. 5 x 10(5) K). Unique CDS observations of a macrospicule were reported by Pi ke and Harrison (1997), and several more macrospicule-like solar features h ave now been identified in the polar regions both on the limb and disk. The se show blue- and red-shifted emission on either side of an axis stretching above the limb from a footpoint region on the disk. These observations are interpreted as indicating the presence of a rotating plasma, a sort of sol ar tornado. In the examples studied, the rotation velocities increase with height. The implications for coronal heating models are discussed.