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Maezawa, K.

Publications and source records attributed to Maezawa, K..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2002

Evolution of Ionospheric Convection during a Double Transpolar Arc Phenomenon on February 11, 1999

An evolution of ionospheric convection was studied for a double transpolar arc phenomenon on February 11, 1999. While one transpolar arc split from the auroral oval in the morning sector and drifted duskward, another arc appeared in the evening sector. The convection was investigated with three velocity data sets: E B drift velocities from the ASTRID-2 satellite; Ion Driftmeter data from the DMSP satellites; and Doppler-shift data from the Super-DARN radars. We inferred convection cells from these data sets and found that the number of convection cells changed from three to four as the dominance of IMF changed from a negative By to a positive Bz. Our result suggests that the ionospheric convection that has been so far discussed for various conditions of IMF may be applied even to the cases accompanied by transpolar arcs.

Narita, Y.↗
NASA NTRS1988

The geomagnetic field at 1982 from DE-2 and other magnetic field data

Data from the DE-2 spacecraft are combined with data from the Magsat spacecraft and data from magnetic observatories and magnetic surveys to derive a geomagnetic field model for the period from May 1979 to May 1983. The model is an extension of the Goddard Space Flight Center (12/83) model. The model includes a solution for parameters representing the noncore field, or anomaly bias, at each observatory in the Project Magnet program. A table of these anomalies is presented. The results from this model are compared with those from the IGRF1980 (Peddie, 1982) and the IGRF1987 (Barraclough, 1987).

Langel, R. A.↗
NASA NTRS1978

Dependence of geomagnetic activity on solar wind parameters - A statistical approach

A statistical analysis of a large body of data is used to give a visual representation of the relative influence of each solar wind/IMF parameter on geomagnetic activity. In addition an attempt is made to determine whether geomagnetic indices differ in their response to various solar wind/IMF parameters and to discuss the physical implications of these differences. It is recommended that ample care should be taken about what kind of geomagnetic index is to be used.

Maezawa, K.↗