FLARE MULTI-LINE 2D-SPECTROSCOPY

A small flare was observed at the Teide Observatory on October 5, 1994 . Simultaneous data were obtained at the German Vacuum Tower Telescope (VTT) with the MSDP spectrograph providing high-resolution imaging sp ectroscopy in two chromospheric lines, and the Gregory Coude Telescope (GCT) providing information about the magnetic field. Basic flare cha racteristics are: The area of the flare kernel (less than or equal to 2 x 2 are sec) is similar in H alpha and Ca II 8542 Angstrom. The earl y phase of the flare is characterized by a blue asymmetry in H alpha a nd a red one in Ca II 8542 Angstrom line. The evolutions of line profi les are different; the red asymmetry observed in the Ca II line is det ected a few seconds later in H alpha. The maximum asymmetry of the Ca II line does not coincide with the maximum brightness. The flare occur s in a region of a strong horizontal gradient of the line-of-sight com ponent of the magnetic field. Brightness and asymmetry in H alpha and Ca II are discussed in the context of standard flare models and veloci ty fields. Our observations suggest that a magnetic reconnection could occur at low levels of the solar atmosphere.