Halo CME Mail

Date: Thu, 16 Aug 2001 17:04

From: Gareth Lawrence

Subject: Full Halo CME on 2001/08/14, probably frontsided

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

UCMEO 93001 10816 2000/
10814 71608 92142 0001/ 360// 223// 30415
10814 71319 91319 41026 ///// 2222/
99999

PLAIN

BT

LASCO and EIT 'observed' a full halo CME on 2001/08/14. Due to an
instrument problem all LASCO data and all EIT 195 A data between
approx 01:30 and 15:30 UT is permanently lost. The event was
first observed in C3 at 16:08 UT as a full halo event with the
leading edge some halfway through the C3 field of view. The
plane of sky speed of the front was measured as 415 km/s at
PA 180 (SP) with no significant acceleration through the
subsequent limited part of C3's field of view.

The CME was most probably associated with an eruptive filament
liftoff. No 195 A EIT images are available but the 304 A images
from the synoptic sets (taken four times daily) show a filament
present at 07:19 UT, erupting at 13:19 UT and vanished by 19:19
UT. If the CME speed quoted above is taken to be constant then
extrapolating the leading edge back to 1 Rs gives an eruption
time of 13:16 UT, which is consistent with the EIT observations.
The centroid of this filament was located at N26W10.
Neither an EIT wave nor a dimming were observed in conjunction
with the CME.

Images and movies of this event are available at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20010814

Apologies for the belated notification of this CME

Best wishes,
        Gareth Lawrence.

++
| Gareth Lawrence,                   E-mail:grl@kreutz.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       |
++