AAS 203rd Meeting, January 2004
Session 48 Fully Employed Stars
Poster, Tuesday, January 6, 2004, 9:20am-6:30pm, Grand Hall

## [48.02] Radio Bursts on the Flare Star AD Leo from the Arecibo Observatory

R. A. Osten, T. S. Bastian (NRAO, Charlottesville)

We discuss recent observations of the M dwarf flare star AD~Leo taken with the Arecibo Observatory. The wide bandwidths currently available (\nu\rm eff ~ 500 MHz) are a factor of >10 improvement over previous investigations of highly circularly polarized, high brightness temperature bursting phenomena. The large degrees of circular polarization (\pic arrow ±100%), coupled with large inferred brightness temperatures (Tb \geq1016K), suggest a coherent emission mechanism, but interpretation has been hindered by narrow bandwidths (\Delta \nu/nu \leq few percent). We find evidence of drifting structures, whose drift rates are compatible with the range from solar type III bursts. We present a summary of the burst characteristics, and interpret the data in the framework of different coherent emission mechanisms.

RAO gratefully acknowledges support from a Jansky fellowship at NRAO.

Bulletin of the American Astronomical Society, 35#5
© 2003. The American Astronomical Soceity.