SOHO/LASCO HALO CME 110906b

UCMEO 93001 10907 1700/
10906 62305 80618 3201/ 319// 323// 40626
10906 62215 82300 41814 11283 1112/
99999

PLAIN

SOHO/LASCO observed a second HALO CME on September 6, 2011.  Event is
first seen in C2 at 23:05 UT with a bright loop over the NNW which
is already out to 3.5 Rsun in first frame. Event propagates to a full
halo by 23:24 UT.  The event continues into the C3 field beginning 23:30
to 06:18 UT out to 21 Rsun.
This SEP event produced proton particles seen in the LASCO white light images. 

Time/height measurements were marked at 5 points in C2 with speeds of 758.0 Km/sec
at position angle 241 degrees. The event is marked to 9 points in C3 where it slightly
slows.  Speeds average through both fields to 626.3 Km/sec at PA 246 degrees, 
acceleration -23.3 m/sec^2. 

SDO/AIA 193 shows a flare of AR 11283 22:15-23:0 UT located at [N14 W18] with a
wave over the north and west hemispheres
STEREO:
COR2 A, 22:39 UT, in east expanding.
Preliminary height/time measure was taken on COR2 A beacon data showing 1046.4 km/sec
COR2 B, 02:25 UT, in the west, first frame as event was already in progress at 23:39.
NOAA reports a X.2 xray flare of AR 11283 22:12-22:24 UT.  An increase in proton flux
is shown, the 10 MeV levels very close to storm conditions.

This is most probably the cause of the 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/2011/110906b/

Best regards,

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

BT