SOHO/LASCO HALO CME 110906

UCMEO 93001 10906 1800/
10906 60224 81018 3371/ 376// 223// 40458
10906 60145 80227 40714 11283 1112/
99999

PLAIN

SOHO/LASCO observed a HALO CME on September 6, 2011.  Event is
first seen in C2 at 02:24 UT with a rough scattered LE front over the NNW
at PA 337. Fainter material expands across the NE and at lower latitudes
across the south hemisphere. The event continues into the C3 field
beginning 03:31 to 10:18 UT where it dissipates and overtaken by another
emission in the NW.
This SEP event produced proton particles seen in the LASCO white light images. 

Time/height measurements were marked at 7 points in C2 with speeds of 693.3 Km/sec
at position angle 337 degrees. The event is marked to 6 points in C3 where it slightly
slows.  Speeds average through both fields to 457.9 Km/sec at PA 322 degrees, 
acceleration -16.5 m/sec^2. 

SDO/AIA 193 shows a flare of AR 11283 01:45-02:27 UT located at [N14 W07] with a
wave over the N and NW hemisphere.
STEREO:
COR2 A, 02:24 UT, in east, expanding north with spray from the south.
Preliminary height/time measure was taken on COR2 A beacon data showing 512.6 km/sec
COR2 B, 02:25 UT, in the west loop with cavity and core in NW and spray across the SW.
Preliminary height/time measure was taken on COR2 B beacon data showing 465.5 km/sec.
NOAA reports a M5.3 xray flare of AR 11283 01:35-02:05 UT.  An small increase in proton 
flux is shown.

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/2011/110906/

Best regards,

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

BT