NASA Scientific and Technical Aerospace Reports

surprising results. This model for the first time shows, that the boundary between the fast and the slow solar wind as observed
by Ulysses beyond 1 AU, is established in the low corona. The fastest wind observed by Ulysses (680-780 km/s) originates
from the polar coronal holes at 70 -90 deg. latitude at the Sun. Rapidly diverging magnetic field geometry accounts for the
fast wind reaching down to a latitude of +/- 30 deg. at the orbit of Earth. The gradual increase in the fast wind observed by
Ulysses, with latitude, can be explained by an increasing field strength towards the poles, which causes Alfven wave energy
flux to increase towards the poles. Empirically, there is a direct relationship between this gradual increase in wind speed and
the expansion factor, f, computed at r greater than 20%. This relationship is inverse if f is computed very close to the Sun.
Author
Magnetic Field Configurations; Magnetohydrodynamics; Two Dimensional Models; Solar Corona; Solar Wind; Astronomical
Models
20040047256 NASA Marshall Space Flight Center, Huntsville, AL, USA
A Measure from Line-of-Sight Magnetograms for Prediction of Coronal Mass Ejections
Falconer, D. A.; Moore, R. L.; Journal of Geophysical Research; 2003; 0148-0227; Volume 108, No. A10; 7 pp.; In English;
Copyright; Avail: Other Sources
From a sample of 17 vector magnetograms of 12 bipolar active regions we have recently found (1) that a measure of the
overall nonpotentiality (the overall twist and shear in the magnetic field) of an active region is given by the strong shear length
Lss, the length of the portion of the main neutral line on which the observed transverse fields is strong (greater than 150 Guass
(G)) and strongly sheared (shear angle greater than 45 degrees), and (2) that L(sub ss) is well correlated with the coronal mass
ejection (CME) productivity of the active regions during the plus or minus 2-day time window centered on the day of the
magnetogram. In the present paper, from the same sample of 17 vector magnetograms, we show that there is a viable proxy
for L(sub ss) that can be measured from a line-of-sight magnetogram. This proxy is the strong gradient length L(sub SG), the
length of the portion of the main neutral line on which the potential transverse field is strong (greater than 150 G), and the
gradient of the line-of-sight field is sufficiently steep (greater than approximately 50 G/Mm). In our sample of active regions,
L(sub SG) is statistically significantly correlated with Lss (correlation confidence level greater than 95%), and L(sub SG) is
as strongly correlated with active region CME productivity as is L(sub SS) (correlation confidence level approximately
99.7%). Because L(sub SG) can be measured from line-of-sight magnetograms obtained from conventional magnetographs,
such as the magnetograph mode of the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory,
it is a dependable substitute for L(sub SS) for use in operational CME forecasting. In addition, via measurement of L(sub SG),
the years-long, nearly continuous sequence of 1.5-hour cadence full disk line-of-sight magnetograms from MDI can be used
to track the growth and decay of the large-scale nonpotentiality in active regions and to examine the role of this evolution in
active region CME productivity.
Author
Coronal Mass Ejection; Line of Sight; Magnetic Signatures; Space Weather; Solar Physics
20040047278 Communications Research Lab., Japan
Review of the Communications Research Laboratory, Volume 48, No. 4
December 2002; ISSN 0914-9279; 164 pp.; In Japanese; Copyright; Avail: Other Sources
Contents include the following: Research on a System for Monitoring, Analyzing, and Forecasting of the Space
Environment. Ionosphere and Thermosphere. Solar and solar wind. Mission and observation of interplanetary Coronal Mass
Ejection (CME).Solar wind plasma instrument for the L5 mission. Forecast tool using Java Script for predicting arrival time
of interplanetary disturbances to the Earth. Real time data reception of ACE and IMAGE satellites. Prediction of the Dst index
from solar wind parameters by a neural network method. Real time geomagnetic data acquisition from Siberia region and its
application. Quasi-real time geomagnetic data transfer from near northern magnetic pole region. Development of instruments
for imaging of the resonance scattering emission from oxygen ion (O II:83.4nm). Ionosphere and thermosphere. Ionospheric
observation and observation information processing system. Space environment information service system.Development of
telephone service system. Space weather forecast in the future manned space era. Correcting instable signal in near-field
antenna gain measurement.
CASI
Advanced Composition Explorer; Data Acquisition; Imaging Techniques; Solar Wind; Telephones; Weather Forecasting
20040047283 Alabama Univ., Huntsville, AL, USA
Forecasting Coronal Mass Ejections from Magnetograms
Falconer, D. A.; Balasubramanian, S.; Moore, R. L.; Gary, G. A.; January 2004; 1 pp.; In English; Living With a Star
Workshop, 23-26 Mar. 2004, Boulder, CO, USA; No Copyright; Avail: Other Sources; Abstract Only
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