A very strong Brackett-gamma hydrogen emission line, and the 2.3 micron CO stellar absorption feature were measured in NGC 253. The presence and strength of the CO feature indicates that late type giant stars produce most of the 2.2 micron continuum emission, while the rate of ionization implied by strength of the Brackett-gamma line indicates that much, perhaps all, of the luminosity detected at far infrared wavelengths originates from a large number of OB stars. As compared to the...
Topics: NASA Technical Reports Server (NTRS), EMISSION SPECTRA, GALAXIES, H GAMMA LINE, CARBON MONOXIDE,...
The author discusses the morphology of luminous Infrared Astronomy Satellite (IRAS) galaxies. A few comments are made about the direction to be taken in future observations of luminous IRAS galaxies.
Topics: NASA Technical Reports Server (NTRS), GALACTIC NUCLEI, GALACTIC STRUCTURE, INFRARED RADIATION,...
Slit spectra, spectrophotometric scans and infrared broad band observations are presented. Eight of the program galaxies can be classified as Seyfert galaxies. Arguments are given that thermal, nonthermal and stellar radiation components were present. One group of Seyfert galaxies was characterized both by the presence of a high density region of gas and by a continuum dominated by nonthermal radiation. The continua of the remaining program Seyferts, which did not have a high density region of...
Topics: NASA Technical Reports Server (NTRS), GALAXIES, INFRARED SPECTROPHOTOMETERS, MARKARIAN GALAXIES,...
Observations of the luminosity sensitive CO absorption band at 2.3 micron are presented for the nuclei of 16 epsilon and SO galaxies. Preliminary data on the radial variation of the CO index in 6 galaxies are also given. The data show that the 2-u radiation from the nuclei is dominated by high luminosity stars of integrated spectral type later than K5. There is only a small variation in the CO absorption from galaxy to galaxy, and only a slight variation with measuring aperture size from 17.5...
Topics: NASA Technical Reports Server (NTRS), CARBON MONOXIDE, GALAXIES, SPECTRAL BANDS, STAR DISTRIBUTION,...
The H 2 region H2-3 has been found to have a large infrared flux with a luminosity of 100,000 to 200,000 solar luminosity between 1.65 and 25 microns. Most of this flux comes from a single component with the diameter of 110 in; (2 pc). At 2.2 microns there is an unresolved source which is identified as the exciting star of the nebula; it can provide the required ionization and the total luminosity observed at infrared wavelengths. The 3- to 25- microns radiation is shown to be consistent with...
Topics: NASA Technical Reports Server (NTRS), H LINES, INFRARED RADIATION, LUMINOSITY, COSMIC DUST,...
First results are presented of observations of a lunar occultation of the solar limb made from the Kuiper Airborne Observatory in the 30 micrometr, 50 micrometer, 100 micrometer, and 200 micrometer continuum during the total solar eclipse of 1981 July 31. The solar limb was extended at the longer wavelengths up to 1000 km higher than predicted from smooth plane-parallel chromospheric models. Results at both second and third contact show the infrared limb extensions to be approximately...
Topics: NASA Technical Reports Server (NTRS), SOLAR ECLIPSES, SOLAR LIMB, SUBMILLIMETER WAVES, C-141...
Eight flights of the Kuiper Airborne Observatory (KAO) were devoted to solar observation. The successful observation of a total solar eclipse was accomplished. The observations were made simultaneously at 30, 50, 100, and 200 microns. The successful adaptation of the KAO for solar observations thus provided the most detailed data to date in this spectral band. The results from a preliminary analysis of the KAO data are summarized: (1) the 200 micron limb is extended about 3 arc sec above the 30...
Topics: NASA Technical Reports Server (NTRS), C-141 AIRCRAFT, LIMB DARKENING, LUMINOUS INTENSITY, SOLAR...
Thirty, 50, 100, and 200 microns solar limb intensity profiles determined with arcsecond resolution from airborne observations of the occultation of the solar limb during the total eclipse of 1981 July 31 are presented. Two points of particular importance emerge: (1) the longer-wavelength (100 and 200 micron) limbs are significantly brighter than disk center. At 200 microns the extreme limb is about 1.22 times the brightness of disk center. This is consistent with the 6000 K temperature-plateau...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, FAR INFRARED RADIATION, LIMB BRIGHTENING, SOLAR...
The bright infrared sources W51-IRS2 has at least three components with different physical and evolutionary properties. The spatial distribution and the near infrared spectra of the components in IRS2 are remarkably similar to, but more luminous than those found in Orion, where an H2 region of comparable linear size is also located close to a cluster of compact infrared sources. The characteristics of the nearby W51-NORTH H2O maser source, and the detection of 2 micro m H2 quadrupole emission...
Topics: NASA Technical Reports Server (NTRS), INFRARED RADIATION, MOLECULAR CLOUDS, NEBULAE, RADIATION...
New observations of the 10 and 20 micron size of the emission region in Arp 220 are presented. Also given are ground based photometry from 1 to 32 micron including measurements of the strength of the silicate feature at 10 micron. The results show that the 20 micron size of Arp is smaller than 1.5 arcsec (500 pc); comparison of IRAS and ground based observations show that IRAS 12 micron flux measured with a large arcmin beam is the same as that seen from the ground with a 3 arcsec aperture. At...
Topics: NASA Technical Reports Server (NTRS), ACTIVE GALACTIC NUCLEI, COSMIC DUST, SEYFERT GALAXIES, SPACE...
Observations of Cygnus X-3 were carried out at 2.5 - 7.5 keV, 2.2 micron, 8.1 GHz and 2.7 GHz over a two week period. The X-ray data show the periodic structure which is typical of Cyg X-3. At times the X-ray and infrared measurements show very similar periodic structure, both in phase and shape, while at other times the infrared data show no periodic variability. The radio fluxes were usually low during the period of observation; both the daily average radio flux levels and spectral index...
Topics: NASA Technical Reports Server (NTRS), CYGNUS CONSTELLATION, INFRARED ASTRONOMY, RADIO ASTRONOMY, X...
The infrared bright galaxy 0421+040P06 detected by IRAS at 25 and 60 microns was studied at optical, infrared, and radio wavelength. It is a luminous galaxy with apparent spiral structure emitting 4 x 10 to the 37th power from far-infrared to optical wavelengths. Optical spectroscopy reveals a Seyfert 2 emission line spectrum, making 0421+040P06 the first active galaxy selected from an unbiased infrared survey of galaxies. The fact that this galaxy shows a flatter energy distribution with more...
Topics: NASA Technical Reports Server (NTRS), ACTIVE GALAXIES, EMISSION SPECTRA, ENERGY DISTRIBUTION,...
