No. 148,
Slow Magnetoacoustic Waves in Two-Ribbon Flares,
by V. Nakariakov and I. Zimovets.
Wave dynamics explains arcade development.
http://sprg.ssl.berkeley.edu/~tohban/wiki/index.php/Slow_Magnetoacoustic_Waves_in_Two-Ribbon_Flares
Older Nuggets are available at
http://sprg.ssl.berkeley.edu/~tohban/wiki/index.php/RHESSI_Science_Nuggets
(the new series), and at
http://sprg.ssl.berkeley.edu/~tohban/nuggets/
(the original series).
We publish these at roughly two-week intervals and welcome
contributions, which should be at least loosely related to RHESSI
science.