caa a22 4500 445345640 CHVBK 20180317142828.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s11207-010-9674-5 doi (NATIONALLICENCE)springer-10.1007/s11207-010-9674-5 Determining the Solar Source of a Magnetic Cloud Using a Velocity Difference Technique [Elektronische Daten] [L. Harra, C. Mandrini, S. Dasso, A. Gulisano, K. Steed, S. Imada] For large eruptions on the Sun, it is often a problem that the core dimming region cannot be observed due to the bright emission from the flare itself. However, spectroscopic data can provide the missing information through the measurement of Doppler velocities. In this paper we analyse the well-studied flare and coronal mass ejection that erupted on the Sun on 13 December 2006 and reached the Earth on 14 December 2006. In this example, although the imaging data were saturated at the flare site itself, by using velocity measurements we could extract information on the core dimming region, as well as on remote dimmings. The purpose of this paper is to determine more accurately the magnetic flux of the solar source region, potentially involved in the ejection, through a new technique. The results of its application are compared to the flux in the magnetic cloud observed at 1 AU, as a way to check the reliability of this technique. We analysed data from the Hinode EUV Imaging Spectrometer to estimate the Doppler velocity in the active region and its surroundings before and after the event. This allowed us to determine a Doppler velocity ‘difference' image. We used the velocity difference image overlayed on a Michelson Doppler Imager magnetogram to identify the regions in which the blue shifts were more prominent after the event; the magnetic flux in these regions was used as a proxy for the ejected flux and compared to the magnetic cloud flux. This new method provides a more accurate flux determination in the solar source region. Springer Science+Business Media B.V., 2010 Coronal mass ejections: interplanetary nationallicence Coronal mass ejections: low coronal signatures nationallicence Harra L. UCL—Mullard Space Science Laboratory, Holmbury St. Mary, RH5 6NT, Dorking, Surrey, UK aut Mandrini C. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut Dasso S. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut Gulisano A. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut Steed K. UCL—Mullard Space Science Laboratory, Holmbury St. Mary, RH5 6NT, Dorking, Surrey, UK aut Imada S. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara-shi, 229-8510, Kanagawa, Japan aut Solar Physics Springer Netherlands 268/1(2011-01-01), 213-230 0038-0938 268:1<213 2011 268 11207 https://doi.org/10.1007/s11207-010-9674-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11207-010-9674-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Harra L. UCL—Mullard Space Science Laboratory, Holmbury St. Mary, RH5 6NT, Dorking, Surrey, UK aut NATIONALLICENCE 700 1- Mandrini C. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Dasso S. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Gulisano A. Instituto de Astronomía y Física del Espacio, CONICET-UBA, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Steed K. UCL—Mullard Space Science Laboratory, Holmbury St. Mary, RH5 6NT, Dorking, Surrey, UK aut NATIONALLICENCE 700 1- Imada S. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara-shi, 229-8510, Kanagawa, Japan aut NATIONALLICENCE 773 0- Solar Physics Springer Netherlands 268/1(2011-01-01), 213-230 0038-0938 268:1<213 2011 268 11207 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer