YOHKOH SXT OBSERVATIONS OF A CORONAL MASS EJECTION NEAR THE SOLAR SURFACE/

We report the observations of a coronal mass ejection (CME) using the Soft X-ray Telescope on board the Yohkoh Mission, The CME had the fami liar three part structure (frontal loop, prominence core and a cavity) . The erupting prominence was observed by the Nobeyama radioheliograph . We were able to determine the mass of the CME (2.6 X 10(14) g) from X-ray observations which seems to be at the lower end of the range of CME masses reported before from white light observations. This is the first time the mass of a CME has been determined from X-ray observatio ns. The height of onset of the CME was 0.3R.. The CME moved much faste r than the erupting prominence while its acceleration was smaller than that of the erupting prominence.