Submission_time: 2013/04/22 06:17 EST

Badge_Name:Roberto Susino

Affiliation:INAF - Osservatorio Astrofisico di Torino

Working_Group 1st Choice:WG1

Working_Group 2nd Choice:WG3

Title:Study of a geoeffective Coronal Mass Ejection with UV spectroscopy and stereoscopic data

Abstract:We study the three-dimensional kinematics of a Coronal Mass Ejection (CME) using data acquired with the Ultraviolet Coronagraph Spectrometer (UVCS) on board SOHO and the COR1 coronagraphs and EUVI telescopes on board STEREO.
The event occurred on May 20, 2007, and was a partial-halo CME associated with a prominence eruption originating from an AR located approximately at the disc center and with a B9 class flare.
The CME produced an interplanetary magnetic cloud which was observed in situ by STEREO and WIND and which appeared to have interacted strongly with the ambient solar wind and triggered minor geomagnetic storms since May 22.
Information on the 3D expansion of the CME provided by STEREO/COR1 data have been combined with spectroscopic observations by SOHO/UVCS.
First results show that line-of-sight velocities derived from spectroscopic data are not fully in agreement with those derived previously with stereoscopic techniques, and this makes evident possible limitations of these techniques.
Our observational results suggest that spectroscopy can provide further constraints for the determination of the real direction of propagation as well as the real speed of a CME, fundamental issues for space weather forecasting and predictive space applications.