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Delamere, Alan

Publications and source records attributed to Delamere, Alan.

Low cost missions to explore the diversity of near Earth objects

We propose a series of low-cost flyby missions to perform a reconnaissance of near-Earth cometary nuclei and asteroids. The primary scientific goal is to study the physical and chemical diversity in these objects. The mission concept is based on the Pegasus launch vehicle. Mission costs, inclusive of launch, development, mission operations, and analysis are expected to be near $50 M per mission. Launch opportunities occur in all years. The benefits of this reconnaissance to society are stressed.

Belton, Michael J. S.

A high radiometric performance CCD for the third generation stratospheric aerosol and gas experiment

A third-generation SAGE instrument is about to be designed as part of the NASA Earth Observational System. Previous instruments have used individual diodes as detectors. The new instrument will use a custom design CCD to dramatically enhance the study of the gas and aerosol components of the upper atmosphere. The CCD is a 3 by 400 imaging array that has a single serial register and an exposure control drain. It will be used at the focal plane of a spectrometer covering the spectral range from 288 nm to 1.02 micron.

Delamere, Alan

Quantum efficiency measurements of Tektronix backside thinned CCDs

Results are presented of a program in progress to produce CCDs with high stable quantum efficiency (QE). Measurements made at 253.7 nm over a six-month period showed no significant QE difference between two CCDs manufactured in 1989 and one manufactured in 1988. QE improvement by the addition of a two-layer antireflection coating is about threefold at 400 nm.

Delamere, Alan

Radiation test results on TK 1024 CCDs

Results are presented from tests on TK 1024 CCDs with a multipinned phase (MPP) implant built into an experiental mask set. The average dark current as a function of temperature increased by a factor of about 3 for the 5 krads of gammas, which is a 10-fold increase for the extra 2 krads of protons. Histograms of the dark current show two types of dark current, an average level change, and dark current spikes.

Delamere, Alan