Halo CME MailHalo CME Mail Date: Fri, 12 Sep 2003 17:53 From: Gareth Lawrence Subject: Partial Halo CME on 2003/09/11, frontsided UCMEO 93001 30912 2300/ 30911 62206 91018 1261/ 297// 233// 40386 30911 62048 92324 2//// ///// 2112/ 99999 PLAIN BT LASCO and EIT observed a partial halo CME on 2003/09/11. A narrow bright loop was first seen in C2 at 22:06 UT in the SE; by 00:30 UT the front spanned ~170 deg from PA 126-297, though faint in the W. The front first appeared in the SE in C3 images at 23:18 UT and reached its maximal extent by 03:18 UT. The mean plane-of-sky speed was 386 km/s, measured at PA 170 with no compelling evidence for acceleration. The CME was probably associated with an eruptive filament which EIT observed primarily between 20:28 - 23:24 UT, though the reorganisation of the affected region of the low corona continued for a substantial period thereafter. The filament extended from S16E24 - S16W11. SEC records a B7.9 X-ray flare between 20:16 - 00:08 UT with peak emission at 22:37 UT, which may be associated with this eruption (no spatial information is given). Both a wave and dimming were observed in conjunction with this event. Images and movies will be made available as soon as possible at ftp://ares.nrl.navy.mil/pub/lasco/halo/20030911 Best wishes, Gareth Lawrence. +----------PLEASE NOTE NEW EMAIL ADDRESS-----------+ Gareth Lawrence, grl@grace.nascom.nasa.gov SOHO-LASCO Operations Scientist, CUA, MC 682.3, Bldg 26, Rm 001, F: +1-301-286-0264 NASA Goddard Space Flight Center, Greenbelt, MD 20771. P: +1-301-286-2941 ++