Subject: SOHO/LASCO Partial HALO CME 130123

UCMEO 93001 30124 1900/
30123 61400 82230 2591/ 145// 323// 40566
30123 61303 81509 14319 ///// 2112/
99999

PLAIN

SOHO/LASCO observed a Partial HALO CME on January 23, 2013.  Event is first seen in
C2 at 14:00 UT as a loop with cavity and core in the Northeast. The front expands
with extensions PA 259-145 degrees for total coverage of 246 degrees in width.
The event continues into the C3 field beginning 15:06 to 22:30 UT leaving the C3
field of view at 30Rsun in the North. 

Time/height measurements were marked to 6 points in C2 with speeds of 547.9 Km/sec
at position angle 28 degrees. The event is marked to 12 points in C3.  Speeds average
through both fields to 566.3 Km/sec at PA 28 degrees.  Acceleration 6.26 m/sec^s.


SDO/AIA 193 shows a filament channel center located [N19, E43] with activation beginning
11:57 UT.  The filament becomes eruptive 13:03-15:09 UT finishing with post loop arcade.
AIA 304 shows the eruption with a large loop and flaring of the channel on disk. 

STEREO: BEACON Data
COR2 A, 14:24-16:54 UT expanding loops over the East and Northeast hemisphere.
Preliminary time/height measure gives 595.9 km/sec velocity at LE. 
EUVI A, n/a
COR2 B, 14:25-17:40 UT large expanding loop over the West and Northwest.
Preliminary time/height measure gives 552.2 km/sec velocity at LE.  
EUVI B,  A CME over the West limb above the equator beginning 13:16 UT. The event
produces a small wave along the limb.

   
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/2013/130123/

Best regards,

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

BT