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Gautier, T. N.

Publications and source records attributed to Gautier, T. N..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1997

IR observations in gamma-ray blazars

The infrared photometric and spectral observation of five gamma ray blazars in coordination with the energetic gamma ray experiment telescope (EGRET) onboard the Compton Gamma Ray Observatory is reported. The infrared measurements were made with a Cassegrain infrared camera and the mid-infrared large well imager at the Mt. Palomar 5 m telescope. The emphasis is on the three blazars observed simultaneously by EGRET and the ground-based telescope during viewing period 519. In addition to the acquisition of broadband spectral measurements for direct correlation with the 100 MeV EGRET observations, near infrared images were obtained, enabling a search for intra-day variability to be carried out.

Mahoney, W. A.↗
NASA NTRS1996

(abstract) An All Sky Cirrus Confusion Noise Map for WIRE

The Wide Field Infrared Explorer (WIRE) is a Small Explorer (SMEX) satellite scheduled for launch in 1998 which will carry out a sky survey of at least 100 square degrees in the wavelength regions of 9-15(micro)m and 21-27(micro)m with spatial resolution of approximately 20 arcsec and sensitivity exceeding 0.6mJy. At this sensitivity level WIRE observations can be seriously affected by the confusion noise contribution from the infrared cirrus emission, so the WIRE survey must be planned with some knowledge of the expected level of cirrus confusion. Production of a cirrus confusion noise map with 0.5 degree resolution based on the spatial power spectral density of the cirrus emission in the IRAS ISSA data is in progess using the method described by Gauthier, et al. Spectrally resolved power spectra density data is obtained from the ISSA maps with a wavelet transform technique.

Wide Field Infrared Explorer WIRE infrared sky sur↗
NASA NTRS1996

The NASA Space Infrared Telescope Facility

The NASA Space Infrared Telescope Facility (SIRTF) will begin definition phase funding in November of 1996. The instrumentation is being designed to accomodate scientific investigation programs in four key areas: discovery and study of brown dwarfs and super planets, discovery and study of protoplanetary and planetary debris disks, study of ultra-luminous galaxies and active galactic nuclei (AGN) and study of the early universe.

NASA Space Infrared Telescope Facility SIRTF↗
NASA NTRS1996

Compact Outflows Associated With TMC1 and TMC1A

High spatial resolution observations are presented of the compact outflows associated with the young protostars TMC1 (IRAS 04381+2535) in Taurus. Emission in CO (1-0) imaged with the Owens Valley millimeter array shows the outflow lobes to be conical close to the star. Analysis of the outflow dynamics indicates that these objects are low-luminosity versions of the energetic outflows more commonly observed.

stars star formation ISM jets outflows reflection ↗
NASA NTRS1994

IRAS sky survey atlas: Explanatory supplement

This Explanatory Supplement accompanies the IRAS Sky Survey Atlas (ISSA) and the ISSA Reject Set. The first ISSA release in 1991 covers completely the high ecliptic latitude sky, absolute value of beta is greater than 50 deg, with some coverage down to the absolute value of beta approx. equal to 40 deg. The second ISSA release in 1992 covers ecliptic latitudes of 50 deg greater than the absolute value of beta greater than 20 deg, with some coverage down to the absolute value of beta approx. equal to 13 deg. The remaining fields covering latitudes within 20 deg of the ecliptic plane are of reduced quality compared to the rest of the ISSA fields and therefore are released as a separate IPAC product, the ISSA Reject Set. The reduced quality is due to contamination by zodiacal emission residuals. Special care should be taken when using the ISSA Reject images. In addition to information on the ISSA images, some information is provided in this Explanatory Supplement on the IRAS Zodiacal History File (ZOHF), Version 3.0, which was described in the December 1988 release memo. The data described in this Supplement are available at the National Space Science Data Center (NSSDC) at the Goddard Space Flight Center. The interested reader is referred to the NSSDC for access to the IRAS Sky Survey Atlas (ISSA).

Wheelock, S. L.↗
NASA NTRS1993

(abstract) Infrared Cirrus and Future Space Based Astronomy

A review of the known properties of the distribution of infrared cirrus is followed by a discussion of the implications of cirrus on observations from space. Probable limitations on space observations due to IR cirrus.

cirrus infrared space observations astronomy inter↗
NASA NTRS1993

(abstract) Spatial Power Spectral Measurements of IR Cirrus

We have used recently released IRAS Sky Survey Atlas (ISSA) image data to investigate the surface brightness distribution of selected regions of infrared cirrus using power spectral analysis techniques.

cirrus infrared IRAS Sky Survey Atlas brightness d↗
NASA NTRS1993

Cirrus and Future Space Based Astronomy

Astronomical observations from space make possible observations of sensitivity and spatial resolution impossible in the past. This increase in sensitivity will both make possible the observation of new phenomena and will bring observations against limitations not encountered before. This paper discusses the effects that infrared cirrus and diffuse interstellar clouds will have on space based observations. Some special opportunities provided by space observations of cirrus are presented and a partial list of currently planned observations of cirrus by space telescopes is given.

cirrus observations sensitivity stellar clouds spa↗
NASA NTRS1990

The circumstellar environment of TMR-1 - A young, low-mass star in the Taurus molecular ring

Near-infrared camera and Owens Valley millimeter interferometer data are presented that reveal the circumstellar environment of TMR-1 on scales of roughly 1000 AU. TMR-1 is a deeply embedded, young, low-mass star located in a rotating ring of material in the TMC-1/Heiles Cloud 2 region of the Taurus molecular cloud. The stellar wind cavity, as outlined by the extended infrared continuum emission at 2.2 microns, overlaps with the redshifted outflow detected in the (C-12)O data. High-density circumstellar material is seen in (C-13)O in emission and at 2.2 microns in absorption. The morphology suggests the high-density gas may either be part of a 1000 AU disk or may represent infalling material from the molecular cloud core. TMR-1 appears to be in an early wind-clearing phase of protostar formation.

Terebey, S.↗
NASA NTRS1986

MIPS - The Multiband Imaging Photometer for SIRTF

The Multiband Imaging Photometer for SIRTF (MIPS) is to be designed to reach as closely as possible the fundamental sensitivity and angular resolution limits for SIRTF over the 3 to 700 micron spectral region. It will use high performance photoconductive detectors from 3 to 200 micron with integrating JFET amplifiers. From 200 to 700 microns, the MIPS will use a bolometer cooled by an adiabatic demagnetization refrigerator. Over much of its operating range, the MIPS will make possible observations at and beyond the conventional Rayleigh diffraction limit of angular resolution.

Rieke, G. H.↗
NASA NTRS1986

MIPS - The Multiband Imaging Photometer for SIRTF

The Multiband Imaging Photometer System (MIPS) for SIRTF is to be designed to reach as closely as possible the fundamental sensitivity and angular resolution limits for SIRTF over the 3 to 700 microns spectral region. It will use high performance photoconductive detectors from 3 to 200 microns with integrating JFET amplifiers. From 200 to 700 microns, the MIPS will use a bolometer cooled by an adiabatic demagnetization refrigerator. Over much of its operating range, the MIPS will make possible observations at and beyond the conventional Rayleigh diffraction limit of angular resolution.

Rieke, G. H.↗
NASA NTRS1986

IRAS observations of the zodiacal background

IRAS sky survey measurements are used to constrain a model for the interplanetary dust emission. Efforts to date, although hampered somewhat by calibration uncertainties, indicate that the cloud is inclined to the ecliptic by approximately 1.7 deg, with its line of ascending nodes at 70 deg ecliptic longitude. The data is well fit by a dust density distribution presently described in cloud symmetry plane coordinates, where the dust has a gray emissivity and an equilibrium temperature at 1 AU of 280 K.

Good, J. C.↗
NASA NTRS1986

The geometry of the zodiacal dust bands

A program is in progress to use the best available IRAS data to determine the orbital parameters of the ensemble of particles which make up the zodiacal dust bands. Refinements on the early results of Gautier and Hauser include the use of a more complete set of data and improved treatment of ring profile effects due to dispersions in orbital parameters. Results to date include an analysis of the sensitivity of the observable parameters of the dust bands to changes in the orbital parameters of the particle ensemble.

Gautier, T. N.↗
NASA NTRS1985

IRAS observations of the interplanetary dust emission

The Infrared Astronomical Satellite (IRAS) has completed a sensitive, highly redundant survey of the full sky in four broad photometric bands at 12, 25, 60, and 100 micrometers wavelength. The survey measured interplanetary dust emission over elongation angle ranging from 60 to 120 degrees. Bright emission from the main cloud is consistent with optically thin blackbody emission. The grains are evidently quite black, with an 'apparent albedo' of about 0.07. The data show clear evidence for deviation of the dust symmetry surface from the ecliptic plane. Surprising bands of emission were discovered near the ecliptic plane and about ten degrees on either side of it. The heliocentric distance of this material, suggested to be asteroidal in origin, is inferred to be about 2.5 AU from both color temperature and parallax measurements.

Hauser, M. G.↗
NASA NTRS1984

Early results from the Infrared Astronomical Satellite

The discoveries made with the Infrared Astronomical Satellite (IRAS) are reviewed. Findings on large-scale extended infrared emission associated with the solar system and the Galaxy and medium-scale extended infrared emission associated with zodiacal dust bands and infrared cirrus clouds are described. Comets have been found to be much dustier than previously thought. Solid material orbits Vega and other stars, and emission from cool interstellar material has been traced throughout the Galaxy up to the poles. Stars in the process of formation have been detected. The far-infrared sky away from the galactic plane has been found to be dominated by spiral galaxies, some of which emit more than 50 percent and as much as 98 percent of their energy in the infrared.

Neugebauer, G.↗
NASA NTRS1984

The IRAS minisurvey

Before the main Infrared Astronomical Satellite (IRAS) all-sky survey was started, a preliminary survey of 900 sq deg was carried out. Some results from this 'minisurvey' are given here. The completeness of the minisurvey at galactic latitudes from 20 to 40 deg drops sharply at flux densities below 0.4, 0.4, 0.5, and 2.5 Jy at 12, 25, 60, and 100 microns, respectively. The corresponding surface densities of point sources brighter than these flux levels are 1.1, 0.4, 0.65, and 1.25/sq deg, respectively. Outside the galactic plane, the majority of the sources at 12 and 25 microns are stars, while galaxies make up a significant proportion of 60 micron sources. The 100 micron band is dominated by emission from interstellar dust over much of the minisurvey area.

Rowan-Robinson, M.↗