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Trauger, J.

Publications and source records attributed to Trauger, J..

32 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

The Etched Hourglass Nebula MyCn18: II A Spatio-Kinematic Model

We have observed MyCn18, a young Planetary Nebulae with HST/WFPC2 and presented the observational results in an earlier paper. Here we present a detailed spatial/kinematical model of H alpha emission from the nebula.

MyCn18 planetary nebulae AGB stars circumstellar m↗
NASA NTRS1994

The On-Orbit Performance of WFPC2

This paper provides an overview of the characteristics of the second Wide Field and Planetary Camera and some authors' perspectives of its first six months of operation on orbit.

Hubble↗
NASA NTRS1993

Active Mirrors for On-Orbit Alignment of the Second Generation Wide Field and Planetary Camera

This paper describes the assembly level testing and calibration of the Articulating Fold Mirrors (AFMs), and the development of a software tool that generates the commands for adjusting the positions of the Pickoff Mirror Mechanism (PMM) and the AFMs to achieve system level optical alignment. Our experience with the POMM and AFMs through system level calibration and testing of the WFPC-2 instrument is described.

Telescope Articulating Fold Mirrors↗
NASA NTRS1993

Two searches for primeval galaxies

A number of active galaxies are now known at very large redshifts, some of them even have properties suggestive of galaxies in the process of formation. They commonly show strong Ly-alpha emission, at least some of which appears to be ionized by young stars. Inferred star formation rates are in the range approximately = 100-500 solar mass/yr. An important question is: are there radio-quiet, field counterparts of these systems at comparable redshifts? Whereas, we are probably already observing some evolutionary and formative processes of distant radio galaxies, the ultimate goal is to observe normal galaxies at the epoch when most of their stars form. We have, thus, started a search for emission-line objects at large redshifts, ostensibly young and forming galaxies. Our method is to search for strong line emission (hopefully Ly alpha) employing two techniques: a direct, narrow-band imaging search, using a Fabry-Perot interferometer; and a serendipitous long-slit spectroscopic search.

Thompson, D.↗
NASA NTRS1991

A search for primeval galaxies

We are conducting a search for emission-line objects at large redshifts, ostensibly young and forming galaxies. Our method is to search for strong line emission, in particular Ly-alpha, using two techniques: a direct, narrow-band imaging search using a Fabry-Perot interferometer; and a serendipitous long-slit spectroscopic search. Assuming that none of the faint candidates found so far are actually primeval galaxies, we can set the strongest limits to date on the surface density of Ly-alpha-luminous primeval galaxies on the sky. Some of the faint emission line galaxies detected in our survey at z roughly 0.5 - 1 may be representative of the faint blue galaxy population detected in deep continuum imaging surveys.

Thompson, D. J.↗
NASA NTRS1984

Dielectric Fabry-Perot mirror coatings for infrared astronomy

A number of Fabry-Perot (FP) coating designs have been developed specifically for IR astronomy. These have been optimized for uniform reflectance over five contiguous spectral ranges of particular astronomical interest between 1 and 5 microns. Wavelength coverage in individual designs is given by (maximum wavelength/minimum wavelength) greater than 1.4, over which reflective finesse is maintained near 35. Consideration has been made for the peculiar requirements of FP coatings. Visual alignment and testing of the FP has been made convenient by bringing the reflective finesse of the coating at 632.8 nm to the same value as the main IR reflection band. For example, a calcium fluoride FP can be aligned and tested at 632.8-nm He-Ne laser line, with the assurance of a corresponding finesse and spectral resolving power over its IR (3.6-5.1-micron) range. In addition, the FP can be used for IR spectroscopy while being simultaneously monitored and/or actively controlled at the laser wavelength. The potential for the coating itself to degrade the effective surface flatness of the FP through either mechanical stress or thickness nonuniformities is minimized by reducing to a minimum the number and thickness of coating layers. Several of these coatings have been fabricated and are actively in use at a number of observatories.

Trauger, J.↗
NASA NTRS1975

Observations of comet Kohoutek /1973f/ with a ground-based Fabry-Perot spectrometer

Observations of H-alpha, H2O+, and forbidden O I emission lines from comet Kohoutek were made during a 2-month period around perihelion. Analyses of H-alpha line profiles and line intensities indicate that the mean outflow velocity of the hydrogen atoms was 7.8 (+ or - 0.2) km/sec and that the hydrogen atom production rate typically varied (0.4 to 1.4) times 10 to the 29-th power per sec for comet-sun distances between 1 AU and 0.4 AU, respectively. The identification of an H2O+ emission feature in certain H-alpha scans indicates that the H2O ions were moving in a tailward direction with a velocity of 20 to 40 km/sec with respect to the comet nucleus. An upper limit of 1 part in 100 was found for the D/H ratio in the cometary atomic hydrogen cloud.

Huppler, D.↗
NASA NTRS1975

Fabry-Perot observations of comet Kohoutek

Observations of H alpha, H20(+), and emission lines from comet Kohoutek were made. Analyses of H alpha line profiles and line intensities indicate that the mean outflow velocity of the hydrogen atoms was 7.8 + or - 0.2 km s(-1) and that the hydrogen atom production rate varied for comet-sun distances between 1 AU and 0.4 AU. The identification of an H20(+) emission feature in certain H alpha scans indicates that the H20(+) ions were moving in a tailward direction with a velocity of 20 to 40 km s(-1) with respect to the comet nucleus. An upper limit of 1 part in 100 was found for the D/H ratio in the cometary atomic hydrogen cloud.

Roesler, F. L.↗