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Study of a coronal mass ejection using STEREO/SECCHI and SOHO/LASCO observations. Alisson Dal Lago 1 , Bernd Inhester 2 , Luis Eduardo Antunes Vieira 2 1 National Institute for Space Research, Sao Jose dos Campos - SP, Brazil
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Study of a coronal mass ejection using STEREO/SECCHI and SOHO/LASCO observations Alisson Dal Lago1, Bernd Inhester2, Luis Eduardo Antunes Vieira2 1National Institute for Space Research, Sao Jose dos Campos - SP, Brazil 2 Max-Planck-Institute for Solar System Research, Katlenburg-Lindau, Germany
Outline • CME on Jan 8-9, 2007. • SOHO: LASCO C2 (Jan 8, 2007, at 14:54UT, PA 65); LASCO C3 (Jan 8-9, 2007) ; • STEREO: SECCHI COR1 A&B; SECCHI COR 2 A&B; SECCHI HI-1 A. • Solwind – Helios observations • Estimate of CME travel time to Venus x observations • Summary 2007/01/08 2007/01/09 Dal Lago et al., ILWS - 2009
Motivation 2007/01/08 2007/01/09 Schwenn, Dal Lago, Huttunen (Kilpua) and Gonzalez, Ann. Geophys., 2005 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Set of observations • SOHO: LASCO C2 (Jan 8, 2007, at 14:54UT, PA 65); LASCO C3 (Jan 8-9, 2007) ; EIT (did not detect any activity – CME behind the East limb). • STEREO: SECCHI COR1 A&B; SECCHI COR 2 A&B; SECCHI HI-1 A. 2007/01/08 2007/01/09 SECCHI/COR1 B 14:41 UT LASCO/C3 01:42 UT Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 STEREO/SECCHI COR 1 B (1.4-4 solar radii) 2007/01/08 14:41 UT 5º H (solar radii) SOHO LASCO C3 (4-32 solar radii) 2007/01/09 02:42 UT STEREO/SECCHI COR 1 B PA65 5º Time (h) SOHO LASCO C3 PA 65 H (solar radii) Time (h) Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 STEREO/SECCHI COR 1 B (1.4-4 solar radii) 2007/01/08 14:41 UT 5º H (solar radii) STEREO/SECCHI COR 1 B PA65 Dal Lago et al., ILWS - 2009 Time (h)
Coronagraph (2 – 18 solar radii) STEREO/SECCHI COR 1 B (1.4-4 solar radii) 2007/01/08 14:41 UT SOHO LASCO C3 (4-32 solar radii) 2007/01/09 02:42 UT SOHO LASCO C3 PA 65 H (solar radii) STEREO/SECCHI COR 1 B PA 65 Dal Lago et al., ILWS - 2009 Time (h)
Coronagraph (2 – 40 solar radii) STEREO/SECCHI COR 1 B (1.4-4 solar radii) 2007/01/08 14:41 UT STEREO/SECCHI HI-1 A 2007/01/09 H (solar radii) STEREO/SECCHI COR 1 B PA155 Time (h) Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Sun Venus • Coronal Mass Ejection Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Sun Venus Jan 8, 2007 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Sun Venus t1AU = 203 – 20.77*ln(Vexp); (Schwenn et al., 2005) (1) t1AU (Vexp=260km/s) = 87 hours (2) T0.72AU = 0.72* t1AU (3) hence, T0.72AU = 63 hours (4) Vexp 1 AU Venus Vrad Dal Lago et al., ILWS - 2009
Solwind - Helios Sun Venus Quadrature observation of CMEs and corresponding ICMEs using SOLWIND coronagraph and Helios 1 plasma analyzer at heliocentric distance of 0.72+ 0.05 AU, from 1979 to 1982 (adapted from Sheeley et al., 1985). Dal Lago et al., ILWS - 2009
Solwind - Helios * Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Sun Venus Vexp 1 AU Venus Vrad Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Summary • Observed by SOHO’s LASCO C2/C3 and STEREO SECCHI COR1A&B/2A&B and HI1A • Detailed information was extracted using image processing techniques; • CME released in the direction of Venus; • Solwind – Helios comparison • Various methods to predict travel time to Venus: not successful. Dal Lago et al., ILWS - 2009
The CME on Jan 8-9 2007 Acknowledgements The authors would like to acknowledge SOHO LASCO and EIT work team and STEREO SECCHI work team for providing the data used in this work. SOHO is a project of international cooperation between ESA and NASA. STEREO SECCHI data are produced by an international consortium of the Naval Research Lab. (US), Lockheed Martin Solar Astrophysics Lab (US), NASA Goddard Space Flight Center (US), Rutherford Appleton Lab (UK), Univ. of Birmingham (UK), Max-Planck-Institut für Sonnensystemforshung (Germany), Centre Spatiale de Liege (Belgium), Institut d’Optique Théorique et Appliqueé (France), and the Institut d’Astrophysique Spatiale (France). A. Dal Lago would like to acknowledge “Conselho Nacional de Desenvolvimento Científico e Tecnologico – CNPq”, of Brazil, for financial support. Dal Lago et al., ILWS - 2009