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Wilkerson, T.

Publications and source records attributed to Wilkerson, T..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Lidar Measurements of Wind, and Cloud & Aerosol Structures using HARLIE at the WVIOP, Sept/Oct 2000

The holographic scanning lidar HARLIE made continuous measurements of aerosol and cloud one-micron backscatter and derived the horizontal wind speed and direction at cloud height over the ARM (SGP) site during the water vapor campaign WVIOP, September 17 - October 6, 2000. Whenever possible, these measurements were compared with Loran-C winds as measured by the routine launches of Vaisala radiosonde balloons scheduled by the ARM project. Taken overall, the agreement between these two types of observation is excellent, which could be taken merely as a validation of the relatively new HARLIE technique. However, the detailed comparison for a given sonde launch clearly requires that, out of the HARLIE data which are taken all the time at all altitudes, one must select those segments that match the altitude-time trajectory of the sonde. Moreover, the conical HARLIE scan at a 45 deg. elevation angle covers a wide area that is more representative of the average wind conditions above the site than the isolated track of the sonde's ascent. We suggest that the HARLIE instrument offers a more general and improved representation of the horizontal wind profile whenever there is sufficient backscatter by clouds and aerosols for lidar operation. HARLIE is a rugged and compact lidar that operates from aircraft as well as from the ground and has been used in several meteorological campaigns. As a "direct detection" lidar, HARLIE does not require the complexity of a coherent detection system. The data reduction algorithms facilitate the rapid and accurate determination of wind speed and direction at all altitudes. Wind measurements and HARLIE performance data from WVIOP 2000 and other campaigns will be presented.

Schwemmer, Geary↗
NASA NTRS1983

The Shuttle Environment Workshop

Results of shuttle environmental measurement programs were presented. The implications for plasma, infrared and ultraviolet experiments were discussed. The prelaunch environmental conditions, results of key environmental measurements made during the flights of STS 1, 2, 3, 4, and postlanding environmental conditions were covered.

Lehmann, J.↗
NASA NTRS1983

Environmental Measurements Session summaries

Emphasis was placed on data from payloads flown on the subject flights including results from the Induced Environment Contamination monitor (IECM). Brief summaries of the vibroacoustics, loads, electromagnetic and thermal aspects of the environment, as derived from Shuttle system measurements, were presented primarily to indicate where the environment was different than observed and, therefore, where specification changes may be forthcoming. In addition, brief summaries of two somewhat unexpected effects, the vehicle glow and interaction between the low Earth environment and Shuttle payload by materials were presented as an aid in interpreting other environmental data. Papers for each payload/experiment involved in Shuttle flights were presented essentially in flight related chronological order. A significant portion of time was allocated for presentation of IECM data since this payload was flown on STS-2, STS-3, and STS-4 and, therefore, represents the largest data base relative to the contamination environment. Summaries of papers are presented.

Lehmann, J.↗
NASA NTRS1983

Report of the infrared, ultraviolet and space plasma panels

The status of the payload bay and the needs of infrared, ultraviolet and space plasma experiments were discussed. Those measurements important in each area were reviewed. Issues of concern and how these environmental conditions might impact experiments were considered. Several common issues were revealed, and recommendations were made.

Lehmann, J.↗
NASA NTRS1983

Future outlook and comments

The events of the workshop panel sessions are summarized and a synopsis of the future of the shuttle and the shuttle environment is given. Comments and projections in a number of areas addressed include: environmental measurements, contamination effects, orbiter constraints on deployable payloads, documentation and environmental information, ultraviolet experiments, infrared experiments, plasma experiments, and shuttle lidar.

Lehmann, J.↗
NASA NTRS1982

The Shuttle Environment Workshop, executive summary and workshop procedures

One of the main experimental monitors used to determine the environment in the payload bay was the Induced Environment Contamination Monitor. This package of instruments has made environmental measurements during STS flights with a high degree of success. This has shown that the shuttle environment is relatively free of contaminants, except for special instances of increased abundance of methane, water vapor and particulates. Results of these measurements are rapidly becoming more available. In establishing the Shuttle Environment Workshop, the findings were shared with scientific experimenters, users and other individuals who need to know what the Shuttle is like and what experimenters may expect in the payload bay. The Workshop was centered around results obtained from the environmental measurements made on the Shuttle. The program agenda for the workshop is given. The procedures and flow of communications for the workshop are indicated.

Lehmann, J.↗
NASA NTRS1968

Atomic spectroscopy with the shock tube.

Shock tube applications in atomic spectroscopy, discussing relative and absolute line strengths for atomic species, transition probabilities and atomic excitation

Bengtson, R.↗