skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: MAGNETIC FIELD IN ATYPICAL PROMINENCE STRUCTURES: BUBBLE, TORNADO, AND ERUPTION

Journal Article · · Astrophysical Journal
;  [1];  [2];  [3];  [4]
  1. SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)
  2. LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, F-92195 Meudon (France)
  3. IRAP—CNRS UMR 5277, 14, Av. E. Belin, F-31400 Toulouse (France)
  4. CISL/HAO, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States)

Spectropolarimetric observations of prominences have been obtained with the THEMIS telescope during four years of coordinated campaigns. Our aim is now to understand the conditions of the cool plasma and magnetism in “atypical” prominences, namely when the measured inclination of the magnetic field departs, to some extent, from the predominantly horizontal field found in “typical” prominences. What is the role of the magnetic field in these prominence types? Are plasma dynamics more important in these cases than the magnetic support? We focus our study on three types of “atypical” prominences (tornadoes, bubbles, and jet-like prominence eruptions) that have all been observed by THEMIS in the He i D{sub 3} line, from which the Stokes parameters can be derived. The magnetic field strength, inclination, and azimuth in each pixel are obtained by using the inversion method of principal component analysis on a model of single scattering in the presence of the Hanle effect. The magnetic field in tornadoes is found to be more or less horizontal, whereas for the eruptive prominence it is mostly vertical. We estimate a tendency toward higher values of magnetic field strength inside the bubbles than outside in the surrounding prominence. In all of the models in our database, only one magnetic field orientation is considered for each pixel. While sufficient for most of the main prominence body, this assumption appears to be oversimplified in atypical prominence structures. We should consider these observations as the result of superposition of multiple magnetic fields, possibly even with a turbulent field component.

OSTI ID:
22679595
Journal Information:
Astrophysical Journal, Vol. 826, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English