SOHO/LASCO Partial Halo CME 20130418

Halo Alert: halo-message.20130418

Subject: SOHO/LASCO Partial HALO CME 130418

UCMEO 93001 30419 1800/
30418 61824 80432 1821/ 027// 323// 30571
30418 61757 81830 49410 11719 1112/
99999

PLAIN

SOHO/LASCO observed a Partial HALO CME on April 18, 2013. Event is first seen in
C2 at 18:24 UT as a loop appearing on the West. The front expands with extensions
PA 182-27 degrees for total coverage of 205 degrees in width. The event continues
into the C3 field beginning 19:06 to 04:32 UT leaving the C3 field of view at
30Rsun in the West hemisphere.

Time/height measurements were marked to 7 points in C2 with speeds of 545.3 Km/sec
at position angle 285 degrees. The event is marked to 13 points in C3. Speeds average
through both fields to 571.4 Km/sec at PA 285 degrees. Acceleration 0.54 m/sec^s.

SDO/AIA 193A shows a flare on the West limb above the equator 17:57-18:30 UT. This
event produces a wave and dimming over the Northwest quadrant followed by a post arcade.
The flare comes from AR11719 located [N10,W94].

STEREO: BEACON Data
COR2 A, 15:24-19:54 UT data gap. expanding partial halo burst over the East
hemisphere.
Preliminary time/height measure gives 699.6 km/sec velocity at LE.
EUVI A, 15:35-19:55 UT data gap. n/a
COR2 B, 18:54-21:54 UT data gap. Symmetric halo in progress with first frame
at 21:54 UT.
Preliminary time/height measure gives 811.0 km/sec velocity at LE.
EUVI B, n/a

NOAA reports a long duration C6.5 Xray flare of AR 11719 17:56/18:23/19:04 UT.

The observation of this event is considered 'FAIR'. This CME is determined a LIMB event.
This event shows signs of material associated with the wave on the frontside.

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

http://umbra.nascom.nasa.gov/lasco/observations/halo/2013/130418/

Best regards,

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

BT

SOHO/LASCO C2 Diff	SOHO/LASCO C3 Diff	SDO/AIA 193A

STEREO/COR2 BEHIND	SDO/AIA 193A Diff	STEREO/COR2 AHEAD

	STEREO/EUVI AHEAD	STEREO/EUVI AHEAD

Time/Height Velocities and Plots

C2/C3

Click on Links below for additional information.

Halo Alert: halo-message.20130418

MPEG Movies

LASCO Software IDL Save Files (.mvi)