Halo CME Mail

Date: Thu, 12 Apr 2001 11:51:15 -0400 (EDT)

From: Gareth Lawrence

Subject: Full halo CME on 2001/04/11

  ------------------------------------------------------------------------

UCMEO 93001 10412 1700/
10411 61331 91842 0001/ 360// 123// 40750
10411 71325 91500 32722 09415 1212/
99999

PLAIN

BT

LASCO and EIT observed a full halo CME on 2001/04/11. The event
was first observed in C2 at 13:31 UT as a thin bright front in
the SW. The C2 occulting disk was surrounded by 14:06 although
emission over the N and E was faint. The bright front first appeared
in C3 at 14:18 with the C3 occultor surrounded by 15:18. The plane
of sky speed of the fastest region of the front was measured as
750 km/s at PA 232 (W) with significant deceleration through
both coronagraphs.

The most probable source of the CME was an M2.3 X-ray flare in
AR 9415. GOES records the flare between 12:56 and 13:49 UT with
peak emission at 13:26. The flare was observed to peak in EIT
at 13:25. EIT observed dimmings during the event, but no wave.

Images and movies of this event are available at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20010411

Best wishes,
        Gareth Lawrence.

ps LASCO/EIT observed a full halo CME in connection with this
   morning's X2 flare (again from AR 9415) and a report is
   presently being prepared.
++
| 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       |
++