Subject: SOHO/LASCO Partial HALO CME 100314

UCMEO 93001 00316 2230/
00314 60030 80518 1250/ 136// 123// 40352
00313 62324 80400 11516 11054 1112/
99999

PLAIN

SOHO/LASCO C2 and C3 observed a partial HALO CME on March 14, 2010.
The event began in C2 as a wide symmetric loop over the East at 00:30 UT.
As the CME progressed material was seen from PA 250-136 degrees.

The event was seen in C3 at 00:42 to the end of the event at 05:18 UT, tracked
out to 10.5 Rsun. Speeds were calculated and measured at 12 points through
C2 and C3 for an averaged velocity of 352.5 km/sec at PA 24 degrees.
Moves through C2 at 383.3 km/sec and slowed slightly in C3 at 335 km/sec.
This is a complex event with both boundaries of the halo showing cavities but 
with uniform progression at both ends and material between. It is apparent this
is global with multiple release/activations.

EIT sees an activation of 2 regions across transient lines including AR 11054
located at [N15 E16] and a region located [N25 W19] beginning 3/13 23:24 UT.
This produced an EIT wave across both regions with the bulk of AR 11054
traveling east, southeast and the other region traveling west, northwest.  This
may demonstrate the cavities in C2.  Shortly after, a flare is seen from AR 11054
at 23:36 UT. Earlier on the west limb, a region at N28 fiercely lifted off with a
post looping arcade at 15:48 UT.  This may be the trigger of events seen in
the 2 regions at 23:24 UT prior to the flaring of AR 11054.

GOES shows a C1.5 Xray event from AR 11054 at 23:36-23:41 UT.
This flare is most probably associated with the CME observed in the LASCO fields.

EIT and LASCO images, movies, and time/height information for this event is
available on the web at:

http://umbra.nascom.nasa.gov/lasco/observations/halo/2010/100314/

Best regards,

Kevin Schenk
SOHO Mission
EIT and LASCO Operations
NASA-Goddard Space Flight Center, USA

BT