High-latitude electron density observations from the IMAGE radio plasma imager

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dc.contributor.advisorReiff, Patricia H.en_US
dc.creatorHenize, Vance Karlen_US
dc.date.accessioned2009-06-04T06:43:52Zen_US
dc.date.available2009-06-04T06:43:52Zen_US
dc.date.issued2003en_US
dc.description.abstractBefore the IMAGE mission, electron densities in the high latitude, high altitude region of the magnetosphere were measured exclusively by in situ means. The Radio Plasma Imager instrument onboard IMAGE is capable of remotely observing electron densities between 0.01 and 100,000 e-/cm-3 from distances of several Earth radii or more. This allows a global view of the high latitude region that has a far greater accuracy than was previously possible. Soundings of the terrestrial magnetic cusp provide the first remote observations of the dynamics and poleward density profile of this feature continuously over a 60-minute interval. During steady quiet-time solar wind and interplanetary magnetic field conditions, the cusp is shown to be stable in both position and density structure with only slight variations in both. Peak electron densities within the cusp during this time are found to be somewhat higher than predicted. New procedures for deriving electron densities from radio sounding measurements are developed. The addition of curve fitting algorithms significantly increases the amount of useable data. Incorporating forward modeling techniques greatly reduces the computational time over traditional inversion methods. These methods are described in detail. A large number high latitude observations of ducted right-hand extraordinary mode waves made over the course of one year of the IMAGE mission are used to create a three dimensional model of the electron density profile of the terrestrial polar cap region. The dependence of electron density in the polar cap on average geocentric distance (d) is found to vary as d-6.6. This is a significantly steeper gradient than cited in earlier works such as Persoon et al., although the introduction of an asymptotic term provides for basic agreement in the limited region of their joint validity. Latitudinal and longitudinal variations are found to be insignificant. Both the mean profile power law index of the electron density profile and, to a stronger degree, its variance show dependence with the DST index.en_US
dc.format.extent143 p.en_US
dc.format.mimetypeapplication/pdfen_US
dc.identifier.callnoTHESIS PHYS. 2003 HENIZEen_US
dc.identifier.citationHenize, Vance Karl. "High-latitude electron density observations from the IMAGE radio plasma imager." (2003) Diss., Rice University. <a href="https://hdl.handle.net/1911/18539">https://hdl.handle.net/1911/18539</a>.en_US
dc.identifier.urihttps://hdl.handle.net/1911/18539en_US
dc.language.isoengen_US
dc.rightsCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.en_US
dc.subjectAstronomyen_US
dc.subjectAstrophysicsen_US
dc.subjectAtmospheric sciencesen_US
dc.subjectPlasma physicsen_US
dc.titleHigh-latitude electron density observations from the IMAGE radio plasma imageren_US
dc.typeThesisen_US
dc.type.materialTexten_US
thesis.degree.departmentPhysicsen_US
thesis.degree.disciplineNatural Sciencesen_US
thesis.degree.grantorRice Universityen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophyen_US
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