ИСТИНА

Limb eruptive events give a good possibility to interpret spectra and filtergrams from a more simple geometric consideration. We present analysis of an eruptive event took place on the eastern limb on April 21, 2015 which was observed by the Ondrejov horizontal telescope and spectrograph. The eruption of the highly twisted prominence was followed by onset of soft X-ray source. We identified the structures observed in H-alpha spectra with the details on the filtergrams and analysed evolution of Doppler component velocities. The timing and observed characteristics of the eruption were compared with prediction of model based on the twisting of the ropes and the kink instability.