Subject: SOHO/LASCO Partial HALO CME 130206abc

UCMEO 93001 30206 1900/
30206 60024 80618 2561/ 138// 323// 31906
30206 60003 80039 11922 11667 1112/
99999

PLAIN

SOHO/LASCO observed a Partial HALO CME on February 6, 2013.  Event is first 
seen in C2 (A) at 00:24 UT as a narrow oblong loop appearing in the Northeast.
This event has a 2nd system (B) closely following with multi-loops with cavity
and core beginning 00:36 UT. The front expands with extensions PA 256-138 degrees
for total coverage of 242 degrees in width. The event continues into the C3 field
beginning 00:42/00:54 to 06:18 UT leaving the C3 field of view at 30Rsun in the
Northeast. A 3rd system (C) begins 03:12 UT in C2, proceeds through C3
04:06-11:42 UT. This system (C) would not qualify as a halo with total width
calculated at 155 degrees, PA 329 to 124 degrees. This CME will be considered
and the speeds and position of this CME were measured.
 

Time/height measurements for (A) were marked to 2 points in C2 with speeds
of 2417.5 Km/sec at position angle 32 degrees. The event is marked to 5 points
in C3.  Speeds average through both fields to 1906.3 Km/sec at PA 33 degrees.
Acceleration 101.94 m/sec^s.

Time/height measurements for (B) were marked to 2 points in C2 with speeds
of 1222.6 Km/sec at position angle 39 degrees. The event is marked to 8 points
in C3.  Speeds average through both fields to 1175.2 Km/sec at PA 39 degrees.
Acceleration -5.47 m/sec^s.

Time/height measurements for (C) were marked to 9 points in C2 with speeds
of 484.0 Km/sec at position angle 42 degrees. The event is marked to 15 points
in C3.  Speeds average through both fields to 544.6 Km/sec at PA 43 degrees.
Acceleration 6.54 m/sec^s.


SDO/AIA 193A shows a flare of AR 11667 located [N22, E19] 00:03-00:39 UT.  This 
flare produced a dimming of the region with a symmetric wave.  A small filament
along the southeast edge of the 11667 region activates at 00:48 with emission.
A filament channel at location [N21, E27] activates at 00:48 and erupts
02:03-03:36 UT producing flare on disk and a bright post loop arcade. These 3
events are related.

STEREO: BEACON Data
COR2 A, 13:24-06:24 UT data gap, n/a 
EUVI A, 13:25-06:35 UT data gap, n/a 
COR2 B, 17:40-00:40 UT 01:40-04:55 UT data gaps. Two CMEs are seen in the field over
the West and Northwest.
Preliminary time/height measure for (AB) gives 1529.6 km/sec velocity at LE.
Preliminary time/height measure for (C) gives 693.0 km/sec velocity at LE.
EUVI B, 17:46-00:46 UT, 01:46-04:16 UT data gaps, n/a

NOAA reports a C8.7 Xray flare of AR 11667 00:04/00:21/00:41 UT. 
There is also a long duration C1.3 xray flare 02:22/03:16/04:25 which fits with the 
eruptive filament timings.

The observation of this event is considered 'FAIR'. This CME is determined a FRONTSIDED event.
The filament eruption East of AR11667 beginning at 02:03 UT is evidence of the series of
loops seen in the LASCO emission.  This filament material is associated but may not be
Earth bound.

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

http://umbra.nascom.nasa.gov/lasco/observations/halo/2013/130206abc/

Best regards,

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

BT