AAS 207th Meeting, 8-12 January 2006
Session 111 Solar Activity
Poster, Wednesday, 9:20am-6:30pm, January 11, 2006, Exhibit Hall

Previous   |   Session 111   |   Next  |   Author Index   |   Block Schedule

[111.02] The FIP Effect in Dynamic Loops

J. M. Laming (NRL)

The First Ionization Potential (FIP) Effect is the by now well known element abundance anomaly in the solar corona and slow speed wind, whereby elements with FIP below about 10 eV are enhanced in abundance by a factor of approximately 4. We discuss some initial work towards refining and improving the model of Laming (2004, ApJ, 614, 1063) where this phenomenon is explained in terms of the ponderomotive force exerted on ions (but not neutrals) in the chromosphere as Alfven waves excited in the convection zone propagate up towards the corona.

We extend considerations to waves generated in the corona which may leak down into the chromosphere, and to the effect on Alfven waves from both sources of acoustic shocks propagating upwards in the chromosphere. The first is motivated by the observations of loop oscillations and the possibility of coronal heating by Alfven resonance, and the second by the possible observation of FIP fractionation setting in at lower altitudes in the chromosphere than predicted by the original model of Laming.

Work supported by the NRL/ONR Solar Magnetism and the Earth's Environment 6.1 Research Option and by NASA Grant NNG05HL39I.

The author(s) of this abstract have provided an email address for comments about the abstract: laming@nrl.navy.mil

Previous   |   Session 111   |   Next

Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.