Halo CME Mail Date: Thu, 4 Apr 2002 12:43 From: Gareth Lawrence Subject: Partial halo CME on 2002/04/02 ------------------------------------------------------------------------ UCMEO 93001 20404 1630/ 20401 61305 91915 2801/ 110// 223// 40935 ///// ///// ///// ///// ///// ///// 99999 BT LASCO observed a partial halo CME on 2002/04/01. A bright loop front was first seen in C2 at 13:05 UT in the NE, and by 14:05 this front spanned 170 deg from PA 280 to PA 110. The front first appeared in C3 at 13:30 UT and reached its maximal span by 14:15 UT, though emission in the NW is quite faint in both coronagraphs. The mean plane-of-sky speed through both coronagraphs was 935 km/s measures at PA 39, with significant deceleration through both. EIT was not observing at the time so no concurrent images of the disk are available. GOES X-ray activity was at the B-class level in the ~8 hrs prior to the time of CME onset, but increased a little around the time of the event with a C1.3 event peaking at 13:03. No significant filaments seem to have disappeared within a reasonable timeframe. Therefore it appears that the event was backsided, but in the absence of EIT data it cannot be stated categorically that this is the case. Images and movies of this event are available at ftp://ares.nrl.navy.mil/pub/lasco/halo/20020311/ Apologies for the late sending of this report, which is due to recuperation leave. Additionally, there are a few events that took place in the March 6-25 period that were not reported at the time. This is because I was on travel at the time, and no cover was available. These reports will be sent out for reference and completeness in time. 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 | ++