Subject:  SOHO/LASCO Partial HALO CME 110601

UCMEO 93001 10601 2013/
10601 61836 80230 0091/ 205// 323// 40365
10601 61612 81709 23021 11226 1112/
99999

PLAIN

SOHO/LASCO observed a Partial HALO CME on June 01, 2011.  Event is first seen in
C2 at 18:36 UT as an expanding loop over the east with cavity and core.
The front expands with extensions PA 009-205 degrees for a total coverage of
196 degrees over the East hemisphere. The event continues into the C3 field
beginning 19:42 to 02:30 UT out to 20.7 Rsun where it dissipates.

Time/height measurements were marked at 9 points in C2 with speeds of 404.6 Km/sec
at position angle 101 degrees. The event is marked to 9 points in C3 where it
slightly decelerates.  Speeds average through both fields to 365.1 Km/sec at PA 100 degrees.
Acceleration of -8.17 m/sec^s.

SDO/AIA 193 shows a cme begin from AR 11226 [S21, E30] approximately 16:12 UT with a wave
prior to a flare of the AR 11226 16:27-16:30 UT. Emission also with a second flare at 16:50.
STEREO EUVI B beacon data shows flare and dimming beginning at 16:35-17:18 UT in the SW field.
COR2 B cme beginning 18:24 UT with emission expanding over the west hemispheres.
NOAA reports a C2.9 xray flare of AR 11226 16:25-16:31 UT and a C4.1 xray flare of AR 12226
16:51-17:08 UT. 

This is most probably the cause of the Partial HALO event seen in LASCO.

The observation of this event is considered 'GOOD'. This CME is determined a FRONTSIDED event.

Images and movies and time/height information for this event is available on the web at:

http://umbra.nascom.nasa.gov/lasco/observations/halo/2011/110601/

Best regards,

Kevin Schenk
Solar Heliospheric Observatory
EIT and LASCO Operations
NASA-Goddard Space Flight Center, USA

BT