TY - JOUR
T1 - The effect of the relative orientation between the coronal field and new emerging flux: I Global properties
AU - Galsgaard, K.
AU - Archontis, V.
AU - Moreno-Insertis, F.
AU - Hood, A. W.
PY - 2007/9/1
Y1 - 2007/9/1
N2 - The emergence of magnetic flux from the convection zone into the corona
is an important process for the dynamical evolution of the coronal
magnetic field. In this paper we extend our previous numerical
investigations, by looking at the process of flux interaction as an
initially twisted flux tube emerges into a plane-parallel, coronal
magnetic field. Significant differences are found in the dynamical
appearance and evolution of the emergence process depending on the
relative orientation between the rising flux system and any preexisting
coronal field. When the flux systems are nearly antiparallel, the
experiments show substantial reconnection and demonstrate clear
signatures of a high-temperature plasma located in the high-velocity
outflow regions extending from the reconnection region. However, the
cases that have a more parallel orientation of the flux systems show
very limited reconnection and none of the associated features. Despite
the very different amount of reconnection between the two flux systems,
it is found that the emerging flux that is still connected to the
original tube reaches the same height as a function of time. As a
compensation for the loss of tube flux, a clear difference is found in
the extent of the emerging loop in the direction perpendicular to the
main axis of the initial flux tube. Increasing amounts of magnetic
reconnection decrease the volume, which confines the remaining tube
flux.
AB - The emergence of magnetic flux from the convection zone into the corona
is an important process for the dynamical evolution of the coronal
magnetic field. In this paper we extend our previous numerical
investigations, by looking at the process of flux interaction as an
initially twisted flux tube emerges into a plane-parallel, coronal
magnetic field. Significant differences are found in the dynamical
appearance and evolution of the emergence process depending on the
relative orientation between the rising flux system and any preexisting
coronal field. When the flux systems are nearly antiparallel, the
experiments show substantial reconnection and demonstrate clear
signatures of a high-temperature plasma located in the high-velocity
outflow regions extending from the reconnection region. However, the
cases that have a more parallel orientation of the flux systems show
very limited reconnection and none of the associated features. Despite
the very different amount of reconnection between the two flux systems,
it is found that the emerging flux that is still connected to the
original tube reaches the same height as a function of time. As a
compensation for the loss of tube flux, a clear difference is found in
the extent of the emerging loop in the direction perpendicular to the
main axis of the initial flux tube. Increasing amounts of magnetic
reconnection decrease the volume, which confines the remaining tube
flux.
KW - Sun: Corona
KW - Sun: Magnetic Fields
UR - http://www.scopus.com/inward/record.url?scp=35348814406&partnerID=8YFLogxK
U2 - 10.1086/519756
DO - 10.1086/519756
M3 - Article
SN - 0004-637X
VL - 666
SP - 516
EP - 531
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -