Observatoire de Paris Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

Combining Observations and Simulations to Advance our Understanding of Solar Eruptions

Monday 21 June 2010, by Noé Lugaz (Institute for Astronomy, University of Hawaii)

Tuesday 29 June 2010 à 11h00 , Lieu : Salle de confĂ©rence du bât. 17

As solar cycle 24 slowly begins, thanks to the always-expanding float of satellites observing the Sun and the heliosphere, immense progresses can be expected in the forecasting and understanding of space weather, in particular regarding the initiation and propagation of coronal mass ejections (CMEs). To make a full use of the new observation capabilities, numerical simulations are often required, in particular to separate instrumental effects from the observed physical phenomena. This is particularly true for line-of-sight observations, such as coronagraphic and heliospheric images, as well as for in-situ measurements for complex series of CMEs. In this talk, I will discuss recent progresses in determining CME physical properties from white-light images, both in the corona (LASCO) and in the heliosphere (SECCHI) with the help of numerical magneto-hydrodynamics models. I will also discuss how numerical simulations can be used to test and validate existing analysis methods used on real data, and to propose new ones. Finally, I will explore how magneto-hydrodynamics models can help explaining in situ measurements at 1 AU, from isolated and multiple CMEs.