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Monday afternoon heliospheric properties of CMEs. DL: Alexis Rouillard (GMU/NRL/NASA): CME classification as a discussion starter. Slow CMEs: blobs, in-out pairs, blow-out, 3-part CMEs. All from flux ropes - Nobody actually disagreed officially. Fast CMEs: a more complicated mess.
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Monday afternoon heliospheric properties of CMEs • DL: Alexis Rouillard (GMU/NRL/NASA): CME classification as a discussion starter. • Slow CMEs: blobs, in-out pairs, blow-out, 3-part CMEs. All from flux ropes - Nobody actually disagreed officially. • Fast CMEs: a more complicated mess. • Lots of discussion: Is it really possible to classify CMEs using their speed since they form a Gaussian or Gaussian-like distribution? Ok for the classification about impulsive vs. gradual events (Jie Zhang). • All CMEs, even using this impulsive/gradual classification are similar, just depends how high the reconnection happens (Angelos). Or is there still some fundamental differences between AR CMEs and “quiet Sun” CMEs (Tibor)?
CME = flux rope? • Do CMEs or flares come first? • Are all CMEs flux rope? • Brian Wood showed one example of a CME with a clear axis BUT 1 AU reconstruction don’t necessarily give the same axis direction.
CME = flux rope? • What proofs do we have? • Does the axis have to be what appear as the axis in the white-light images? • Can we really infer orientation from density measurements? • We need remote-sensing of the magnetic field, maybe Faraday rotation. • Mario Bisi showed the CME events from August 2010. • 6+ CMEs probably contributed • At 1 AU, VEX and ST-B see a RH flux rope but ACE sees a LH flux rope. Different CMEs? • Alexis mentioned a case from 2008 when STEREO separation was small and 2 events with different helicity arrived at the same time at Earth...
Life without STEREO nor HIs • Brian’s example: clear case when not-halo CMEs are Earth-directed. Clear contribution from the HIs. In theory, only need one continuous monitoring of the heliosphere away from the Sun-Earth line. • Do CMEs rotate? • Evidence from coronagraphs? • What mechanism would cause rotation to start farther away in the heliosphere? • One example of 45+ degree rotation shown by Robin Colaninno. • Jason Byrne showed kinematics from December 2008 CME: different peak speed from Ying Liu’s model. Also discussed problem of determining CME kinematics.