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Miller, George P.

Publications and source records attributed to Miller, George P..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

FNAS lightning detection

A review of past and future investigations into lightning detection from space was incorporated into a brochure. Following the collection of background information, a meeting was held to discuss the format and contents of the proposed documentation. An initial outline was produced and decided upon. Photographs to be included in the brochure were selected. Quotations with respect to printing the document were requested. In the period between 28 March and June 1993, work continued on compiling the text. Towards the end of this contract, a review of the brochure was undertaken by the technical monitor. Photographs were being revised and additional areas of lightning research were being considered for inclusion into the brochure. Included is a copy of the draft (and photographs) which is still being edited by the technical monitor at the time of this report.

Miller, George P.↗
NASA NTRS1993

Chemical release and radiation effects (CRRES) data directory

The following tasks were completed under this contract: a revision and update of the Chemical Release and Radiation Effects (CRRES) data directory was performed taking into account the corrections and suggests for improvements obtained from the participants at the final CRRES IWG meeting held at SAIC on 14-16 Dec. 1992. A draft copy of the report was then circulated to as many as possible of the relevant CRRES Principal Investigators, co-Investigators, and technicians with a request for a final check on accuracy and completion. A copy of the mailing list is given in Appendix A. All corrections and updates received were implemented. A hard copy together with a floppy disk version was forwarded to Richard Howard, NASA Headquarters, who is arranging for the archiving of the CRRES Data Summary at NSSDC. Final copies were sent where possible.

Miller, George P.↗
NASA NTRS1992

FNAS CRRES program completion

An agenda and the list of attendees at the Combined Release and Radiation Effects Satellite (CRRES) IWG meeting, held on 14-15 Dec. 1992, are presented. Short summaries of the work that has been completed to date, in support of the contract, are presented.

Miller, George P.↗
NASA NTRS1992

CRRES: The combined release and radiation effects satellite program directory

As a result of natural processes, plasma clouds are often injected into the magnetosphere. These chemical releases can be used to study many aspects of such injections. When a dense plasma is injected into the inner magnetosphere, it is expected to take up the motion of the ambient plasma. However, it has been observed in previous releases at moderate altitudes that the cloud preserved its momentum for some time following the release and that parts of the cloud peeled off from the main cloud presumable due to the action of an instability. As one moves outward into the magnetosphere, the mirror force becomes less dominant and the initial conditions following a release are dominated by the formation of a diamagnetic cavity since the initial plasma pressure from the injected Ba ions is greater than the magnetic field energy density. A previous high-altitude release (31,300 km) showed this to be the case initially, but at later times there was evidence for acceleration of the Ba plasma to velocities corresponding to 60,000 K. This effect is not explained. This series of experiments is therefore designed to inject plasma clouds into the magnetosphere under widely varying conditions of magnetic field strength and ambient plasma density. In this way the coupling of injected clouds to the ambient plasma and magnetic field, the formation of striations due to instabilities, and possible heating and acceleration of the injected Ba plasma can be studied over a wide range of magnetosphere parameters. Adding to the scientific yield will be the availability of measurements for the DOD/SPACERAD instruments which can monitor plasma parameters, electric and magnetic fields, and waves before, during and after the releases.

Layman, Laura D.↗
NASA NTRS1992

CRRES experiments, data collection, analysis and publication

The tasks undertaken to be performed under this contract included the continued coordination and documentation of the CRRES program and the development of an archive that details the experimental results obtained by the CRRES Program. Details of the work undertaken and results achieved are summarized in the following sections.

Miller, George P.↗
NASA NTRS1992

Chemical Release and Radiation Effects Satellite (CRRES) program archiving and Puerto Rican sounding rocket campaign

The tasks undertaken as part of this contract included the continued coordination and documentation of the CRRES program and the development of an archive that details, in easily accessible form, the experimental results obtained by the CRRES Program. Details of the work undertaken and results achieved are summarized in the following sections. The achievement of this goal is clearly demonstrated in the appendices attached to this report and the success, in both scientific and public relation terms, of the El Coqui rocket campaign.

Miller, George P.↗
NASA NTRS1990

The G value in plasma and radiation chemistry

The application of the G-value concept to plasma chemistry is considered. A general formula which expresses the G value for a general reaction in terms of experimentally controllable parameters is derived by applying simple gas-dynamic theory to a plasma reactor with straight walls. The formula expresses the G value as a function of the electrical power absorbed, the fraction of molecules transformed, and the flow rate of the gas entering the reactor. The formula was applied to the ammonia plasma radio-frequency discharge data of d'Agostino et al. (1981); the results showed that the G(-NH3) value lies in the range of 6.0-20 molecules/100 eV, depending on the conditions. This similarity of the G(-NH3) value with Peterson's (1974) range 2.7-10 found for the gas-phase radiolysis of ammonia, suggests that there might be a common reaction mechanism initiated by inelastic electron-molecule collisions.

Baird, James K.↗