monday afternoon heliospheric properties of cmes
DESCRIPTION
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. - PowerPoint PPT PresentationTRANSCRIPT
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.