HR: 11:05h
AN: SM12A-04    [Abstracts]
TI: An Inner-Magnetospheric Electron Density Database Determined from IMAGE/RPI Passive Dynamic Spectra
AU: * Webb, P A
EM: Phillip.A.Webb@nasa.gov
AF: UMBC/GEST, Code 674 Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Benson, R F
EM: Robert.F.Benson@nasa.gov
AF: NASA, Code 673 Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Denton, R E
EM: Richard.E.Denton@dartmouth.edu
AF: Dartmouth College, Department of Physics, Hanover, NH 03755, United States
AU: Goldstein, J
EM: jgoldstein@swri.org
AF: Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228, United States
AU: Garcia, L N
EM: Leonard.N.Garcia@nasa.gov
AF: QSS, Code 630 Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Reinisch, B W
EM: Bodo_Reinisch@uml.edu
AF: Center for Atmospheric Research, University of Massachusetts at Lowell, Lowell, MA 01854, United States
AB: The magnetospheric electron density (N_e) is a fundamental space-physics parameter. It is often difficult to make N_e measurements to an accuracy better than a factor of two in low-density (N_e ~ 1 cm^-3 or less) space plasmas due to problems associated with spacecraft/plasma interactions which become enhanced in such an environment. Plasma-wave techniques can provide accurate N_e measurements if the wave modes of the received signals can be properly identified. The amplitudes of the signals received by the Radio Plasma Imager (RPI) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) satellite during passive observations are displayed as a function of frequency and time to form a dynamic spectrum. A semi-automated fitting technique has been developed to extract N_e from these dynamic spectra. The fitting method considers physical features found in the dynamics spectra, such as the upper-hybrid band, the continuum edge, and banded emissions. This technique is often able to provide in situ N_e measurements along extended portions of the orbit of IMAGE. With nearly five years of data from 2001 to 2005, the 14-hour orbit of IMAGE resulted in ~ 6000 separate dynamic spectra. This semi-automated method allows the dynamic spectra to be analyzed in a timely manner to determine N_e. The results have been used to form a plasmaspheric N_e database that is being made available to the scientific community.
DE: 2730 Magnetosphere: inner
DE: 2740 Magnetospheric configuration and dynamics
DE: 2768 Plasmasphere
DE: 2788 Magnetic storms and substorms (7954)
DE: 2794 Instruments and techniques
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting