JOP147 Ellerman Bombs and Severny Moustaches Received 30 August 2001 COORDINATORS: Alexander Kosovichev (sasha@quake.stanford.edu, tel. 1-650-723-7667) Serge Koutchmy (koutchmy@iap.fr, tel. 33 1 44 32 80 56) Alexandros Georgakilas (georg@caltech.edu) INSTRUMENTS: MDI, DST, TRACE SCIENCE OBJECTIVES: Severny moustaches or Ellerman bombs are small, short-living sources of peculiar line emission or absorption. They are observed as wide wings of spectral lines, typically asymmetrical, indicating fast jet-like motions. They represent small (1 arcsec) bright structures which appear in solar active regions in preference around sunspots and under Arch Filament Systems (AFS). Their lifetime is between 12-15 min. and they tend to reoccur at the same points (e.g. Georgakilas, et al, 1999). Moustaches are often accompanied by an increase in continuum emission, and sometimes are related to solar flares (Severny, 1968). The physics of these phenomena is not understood. Transient, moustaches-like, phenomena have been recently found during solar flares in the MDI data (Kosovichev and Zharkova, 2001). Our main objective is to obtain spectroscopic observations of moustaches simultaneous with MDI and TRACE in order to better understand the nature of this phenomenon and its relation to flares and coronal jets. OBSERVATIONS: For MDI we plan to run a three-variable campaign in the high-resolution field of view (hr_fe_me_ve) and a line-profile campaign (hr_vel_lp_e2 or hr_mag_lp_e2). If there is no good target in the hi-res field then we run the standard full-disk campaign. The spectroscopic data will be obtained at The Richard B. Dunn Solar Telescope (DST). For coordination with TRACE we would like to run a series of 1600, 171, and wl images. TARGET SELECTION: The target will be an active region in the MDI high-resolution field of view. SCHEDULING: The observations are planned for September 16-23, 2001.