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Carter, B. D.

Publications and source records attributed to Carter, B. D..

Application of remote sensing to state and regional problems

Progress is reported in the following areas: remote sensing applications to land use planning Lowndes County, applications of LANDSAT data to strip mine inventory and reclamation, white tailed deer habitat evaluation using LANDSAT data, remote sensing data analysis support system, and discrimination of unique forest habitats in potential lignite areas of Mississippi. Other projects discussed include LANDSAT change discrimination in gravel operations, environmental impact modeling for highway corridors, and discrimination of fresh water wetlands for inventory and monitoring.

Miller, W. F.↗

Nuclear-pumped CW lasing of the He-Ne system

The gain for the 6328-A laser line for the nuclear excited He-Ne system has been measured to 300 Torr pressure at thermal neutron flux levels from 2 x 10 to the 7th to 1 x 10 to the 14th n/sq cm sec. In order to estimate small:signal gain, the gain was also measured as a function of input intensity. For demonstration of feasibility of CW operation of nuclear pumped lasers, a cavity was operated and lasing was observed. Although the laser output was small, it is concluded that lasing in a CW mode has been achieved with He-Ne using moderate neutron flux levels.

Carter, B. D.↗

CW nuclear pumped lasing of 3He-Ne

The results of a study on the CW nuclear pumped lasing of the He-Ne system are presented. Preliminary experiments measured single pass gain for the 6328.2A laser transition at neutron fluxes up to 1 x 10 to the 14th power neutrons/sq cm sec. Peak gain for a 300 torr (He-3)-Ne (5:1 mixture) was found to be 8.84 dB/meter at a 2 x 10 to the 12th power neutrons/sq cm sec neutron flux. Further experiments measured the gain in the flux region from one million to 2 x 10 to the 12th power neutrons/sq cm sec. In addition, gain vs. probe laser intensity at various neutron fluxes was measured. These measurements resulted in the construction of a laser cavity and the subsequent CW nuclear pumped lasing at 6328.2A in (He-3)-Ne. Experiments were also carried out on the 3.39 micrometer superradiant line in (He-3)-Ne. On three separate occasions, at two different facilities, lasing was observed. Although (He-3)-Ne was found to have the lowest threshold for lasing found so far, it also had the lowest output power on the order of tens of microwatts.

Carter, B. D.↗

Research on radiation induced laser plasmas

The development of high power nuclear pumped lasers is discussed. The excitation mechanism of continuous wave (CW) HeNe nuclear pumped lasers is studied and a CO2 nuclear pumped laser is used to demonstrate the CW output in the order of watts. The assumption that high power densities are only achievable by volume fission fragment sources is used to identify laser gases which are compatible with UF6 by excited states lifetime measurements. The examination of Xe2, XeF, and KrF under nuclear irradiation to determine if they are good candidates for nuclear-pumped lasers is described.

Schneider, R. T.↗

Application of remote sensing to state and regional problems

The author has identified the following significant results. The Lowndes County data base is essentially complete with 18 primary variables and 16 proximity variables encoded into the geo-information system. The single purpose, decision tree classifier is now operational. Signatures for the thematic extraction of strip mines from LANDSAT Digital data were obtained by employing both supervised and nonsupervised procedures. Dry, blowing sand areas of beach were also identified from the LANDSAT data. The primary procedure was the analysis of analog data on the I2S signal slicer.

Miller, W. F.↗

Application of remote sensing to state and regional programs

The problem includes data acquisition and transformation to products acceptable to the users. Optimized institutionalization of data management, product transfer, and education of the user community are also of major concern. With respect to the lattice, various structures were suggested and the fields of application are presented.

Miller, W. F.↗