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Wynn-Williams, C. G.

Publications and source records attributed to Wynn-Williams, C. G..

52 records · Page 3
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NASA NTRS1975

Studies of the infrared source CRL 2688

Infrared, optical, and radio observation are described of a newly discovered galactic infrared source. Most of the radiation comes from a 1.''5 diameter infrared source at a temperature of about 150 K, but some visible emission in the form of a symmetrical highly polarized reflection nebulosity is also seen. The object could represent either a very early or a very late stage in stellar evolution.

Ney, E. P.↗
NASA NTRS1974

Infrared, radio, and X-ray observations of Cygnus X-3

Infrared observations of Cyg X-3 are presented along with X-ray and radio data. A study of the data shows evidence for several types of behavior in the infrared flux variations of Cyg X-3. It is pointed out that a lack of periodic variations observed can be due either to a real absence of these variations or to a masking by an outburst preceding the observation time. There is no simple radio-infrared correlation, although both radio and infrared emissions were observed during the same period of time.

Becklin, E. E.↗
NASA NTRS1974

Infrared emission from H II regions

Analysis of observations made at infrared wavelengths of a large number of H II regions. Several types of IR sources are found associated with H II regions, and a single region can contain a number of varied IR emitting objects. The main sources of IR emission are ionized hydrogen concentrations, heated dust particles, and OH/H2O masers. Flux density maps for both radio and IR emission suggest that there is a physical association between the IR and radio-emitting regions. The properties of several H II regions indicate that they may be protostellar objects at various stages of evolution.

Wynn-Williams, C. G.↗
NASA NTRS1974

Infrared studies of H II regions and OH sources

This paper presents the observational results of a high spatial-resolution mapping and photometric study in the wavelength range from 1.65 to 20 microns of four H II regions and seven OH sources. Infrared emission indicative of the presence of heated dust was found from the compact H II condensations in W51, DR21, and NGC7538. Infrared emission was also found from the positions of maser sources in NGC 7538, W75(N) W75(S) and Sharpless 269, but not from that in W51. An extended infrared source was found coincident with the peculiar OH source OH 0739-14.

Wynn-Williams, C. G.↗
NASA NTRS1974

Accurate positions of OH sources

The Owens Valley interferometer was used at 1665, 1667, and 1720 MHz to measure the positions of eleven OH emission sources. The 1720-MHz OH source in W3 (continuum) was found to be 40 seconds away from the H2O maser source and was found not to coincide with any radio or infrared feature. Two OH emission sources were found in NGC 7538; one is identifiable with a very compact radio infrared source, while the other, 80 seconds to the south, is as yet unidentified. The OH sources 0739-14 and Sharpless 269 also coincide with infrared sources.

Wynn-Williams, C. G.↗
NASA NTRS1973

The size of NGC 1068 at 10 microns

The data presented show that a majority of the 10-micron emission from NGC 1068 comes from an area with a diameter of about 60 pc. The measurements described were made at 10 microns on two nights at the 200-inch Hale telescope. The data obtained agree with the results obtained by Stein et al. (1973). An approach to reconcile the new data with the variability observed by Rieke and Low (1972) is also discussed.

Becklin, E. E.↗
NASA NTRS1973

Infrared and X-ray variability of Cyg X-3.

Coordinated X-ray and IR observations of Cyg X-3 indicate the presence of a 4.8-hr periodicity in the IR flux density which is synchronized with the previously discovered 4.8-hr periodicity in X-ray emission intensity. This uniquely associates the X-ray source with the IR source, and hence, through the positional coincidence, with the radio object. In addition, short-term variability in the IR flux of Cyg X-3 is described which may be related to the flares seen at radio wavelengths. An improved estimate of the X-ray position is also given.

Becklin, E. E.↗
NASA NTRS1973

On the nature of the infrared point source in the Orion Nebula.

New photometric observations of the BN infrared source in the Orion Nebula eliminate the possibility that it is simply a highly reddened star, and undermine the conclusion that there are 80 mag of visual extinction to the source. We suggest that there is a generic relationship between it and the infrared source IRS 5 in the H II region W3.

Becklin, E. E.↗
NASA NTRS1973

Infrared emission from the southern H 2 region H2-3

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 dust heated by L alpha radiation within the nebula, but much of the 40- to 350- microns radiation probably originates from outside the H 2 region.

Becklin, E. E.↗
NASA NTRS1973

New infrared sources associated with H II regions

The H II regions studied have generally been those which contain OH or H2O maser sources and which have been shown to contain compact condensations of ionized gas which may be connected with star formation processes. A brief account of two such sources, W3 and NGC 7538, is given. On the basis of the reported observations it is concluded that in general H II condensations are infrared sources in the range from 3 to 20 microns. The condensations are hidden optically by large quantities of obscuring matter.

Wynn-Williams, C. G.↗
NASA NTRS1973

The spatial distribution of the infrared emission from NGC 7027

Photometric measurements of the planetary nebula NGC 7027 from 4.8 to 20 microns are presented along with a map made at 10 microns with a 1.8-arc-sec aperture. There is an extremely close similarity between the shapes of the sources at 10 microns and at 5 GHz in that each consists of an oval ring with a deep depression in the center, and no evidence for any surrounding low-brightness envelope. However, the optical source displays no evidence for a ring structure and shows very little symmetry. The infrared radiation is discussed in terms of absorption by dust particles of stellar and/or nebular radiation and re-emission of the energy at longer wavelengths.

Becklin, E. E.↗