TY - JOUR
T1 - Benchmarking fast-to-Alfven mode conversion in a cold MHD plasma. II. How to get Alfven Waves through the solar transition region
AU - Hansen, Shelley Candice
AU - Cally, Paul Stuart
PY - 2012
Y1 - 2012
N2 - Alfven waves may be difficult to excite at the photosphere due to low-ionization fraction and suffer near-total reflection at the transition region (TR). Yet they are ubiquitous in the corona and heliosphere. To overcome these difficulties, we show that they may instead be generated high in the chromosphere by conversion from reflecting fast magnetohydrodynamic waves, and that Alfvenic TR reflection is greatly reduced if the fast reflection point is within a few scale heights of the TR. The influence of mode conversion on the phase of the reflected fast wave is also explored. This phase can potentially be misinterpreted as a travel speed perturbation with implications for the practical seismic probing of active regions.
AB - Alfven waves may be difficult to excite at the photosphere due to low-ionization fraction and suffer near-total reflection at the transition region (TR). Yet they are ubiquitous in the corona and heliosphere. To overcome these difficulties, we show that they may instead be generated high in the chromosphere by conversion from reflecting fast magnetohydrodynamic waves, and that Alfvenic TR reflection is greatly reduced if the fast reflection point is within a few scale heights of the TR. The influence of mode conversion on the phase of the reflected fast wave is also explored. This phase can potentially be misinterpreted as a travel speed perturbation with implications for the practical seismic probing of active regions.
UR - http://iopscience.iop.org/0004-637X/751/1/31/
U2 - 10.1088/0004-637X/751/1/31
DO - 10.1088/0004-637X/751/1/31
M3 - Article
SN - 0004-637X
VL - 751
SP - 1
EP - 11
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 1
ER -