Halo CME Mail

Date: Mon, 17 Sep 2001 15:38

From: Gareth Lawrence

Subject: Partial halo CME on 2001/09/17

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UCMEO 93001 10917 2030/
10917 60854 91142 1201/ 260// 213// 30825
10917 60824 90936 20414 09616 2212/
99999

PLAIN

BT

LASCO and EIT observed a partial halo CME on 2001/09/17. The event
was first observed in C2 at 08:54 UT as a narrow bright loop front
in the SE with fainter extensions over the S Pole. By 19:30 UT this
front spanned some 140 deg over the S Pole from PA 120 to PA 260.
The front first appeared in C3 at 09:18 UT with maximal coverage
of the C3 occultor by 10:20 UT. The plane of sky speed of the front
was measured as 825 km/s at PA 174 (SP) with slight deceleration
through both coronagraphs' fields of view.

The CME was most probably associated with an eruptive filament
liftoff which EIT observed from about 08:24 UT to 09:36 UT though
the 08:24 image is not included in the movie since the image is
partial and the data is degraded. In addition, GOES recorded an
M1.5 X-ray flare in AR9616 between 08:18 and 08:34 UT with peak
emission at 08:24. EIT also observed this flare between 08:24 and
08:36, and the northern end of the eruptive filament was rooted
in this active region. SEC places the flare at S14E04 and the
filament ran close to due south from there. A dimming was observed
in association with this event, but no wave.

Images and movies of this event are available at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20010917

Best wishes,
        Gareth Lawrence.
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| 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       |
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