Halo CME Mail

Date: Mon, 9 Apr 2001 15:04:45 -0400 (EDT)

From: Gareth Lawrence

Subject: Full halo CME on 2001/04/09


Status: O

UCMEO 93001 10409 1900/
10409 61554 91842 0001/ 360// 223// 41086
10409 61536 91624 30421 09415 1112/
99999
 
PLAIN
 
BT


LASCO and EIT observed a full halo CME on 2001/04/09. The event 
was first observed in C2 at 15:54 UT as a bright wide front in
the S and SW. The C2 occulting disk was surrounded by 16:30 although
emission over the N pole was faint. The bright front first appeared 
in C3 at 16:18 with the C3 occultor surrounded by 17:18. The plane 
of sky speed of the fastest region of the front was measured as
1086 km/s at PA 214 (W) with no significant deceleration through
both coronagraphs. Note that this speed was inferred fronm the 
limited data available at the time of writing.

The most probable source of the CME was an M7.9 X-ray flare in
AR 9415. GOES records the flare between 15:20 and 16:00 UT with 
peak emission at 15:34. The flare was observed to peak in EIT 
at 15:36. An EIT wave was observed during the event, as was 
dimming. 

Images and movies of this event are available at: 
 
ftp://ares.nrl.navy.mil/pub/lasco/halo/20010409

Best wishes,
        Gareth Lawrence.

++
| Gareth Lawrence,                 E-mail:grl@ajcannon.nascom.nasa.gov |
| SOHO-LASCO Operations Scientist,				       |
| CUA, Mail Code 682.3,                                                |
| NASA Goddard Space Flight Center,      Phone:  +1-301-286-2941       |
| Building 26, Room G-1,                         +1-301-286-3447       |
| Greenbelt, MD 20771.                   Fax:    +1-301-286-0264       |
+