INVESTIGADORES
LOPEZ FUENTES Marcelo Claudio
artículos
Título:
Active region helicity evolution and related coronal mass ejection activity
Autor/es:
L. M. GREEN; M. C. LÓPEZ FUENTES; C. H. MANDRINI; L. VAN DRIEL-GESZTELYI; P. DÉMOULIN
Revista:
ADVANCES IN SPACE RESEARCH
Editorial:
Elsevier Science
Referencias:
Año: 2003 vol. 32 p. 1959 - 1964
ISSN:
0273-1177
Resumen:
The computation of magnetic helicity has become increasingly important
in the studies of solar activity. Observations of helical structures in
the solar atmosphere, and their subsequent ejection into the
interplanetary medium, have resulted in considerable interest to find
the link between the amount of helicity in the coronal magnetic field
and the origin of coronal mass ejections (CMEs), which provide a natural
method to remove helicity from the corona. Recent works have endeavored
to find the source of helicity to explain the observed CME activity in
specific cases. The main candidates being differential rotation, shear
motions or a transfer of helicity from below the photosphere into the
corona. We study an active region for several rotations during 1997 and
1998 to investigate the relative importance of these mechanisms. We find
that photospheric differential rotation cannot provide the required
magnetic helicity to the corona and the ejected CMEs. Localized
photospheric motions can provide a larger helicity flux, though still
not sufficient.