Showing papers by "Charles H. Townes published in 1980"
TL;DR: The first observation of far-infrared molecular line emission from the interstellar medium is reported in this paper, which implies that the region is optically thin in these lines and that much of the carbon is in the form of CO.
Abstract: The first observation of far-infrared molecular line emission from the interstellar medium is reported. Strong emission from the J = 21-20 and J = 22-21 rotational transitions of carbon monoxide was detected in the Kleinmann-Low/shocked H2 region of the Orion Molecular Cloud. The results imply that the region is optically thin in these lines and that much of the carbon is in the form of CO. This work also represents the first use of an antimony-doped germanium photoconductor in an astronomical application.
45 citations
TL;DR: In this paper, a methanol source in OMC-1 has been interferometrically mapped in two masing transitions, the 6/sub 2/..-->..6/sub 1/(E) and 7/sub2/reverse arrow, which have wavelengths near 1 cm.
Abstract: The methanol source in OMC-1 has been interferometrically mapped in two masing transitions, the 6/sub 2/..-->..6/sub 1/(E) and 7/sub 2/reverse arrow7/sub 1/(E), which have wavelengths near 1 cm. The source was found to consist of 10 components with different Doppler velocities. Most of the components radiate in both of the mapped transitions, and have brightness temperatures or limits of 1000--4000 K. None of the components are resolved in declination, to a limit of 15''. Six of the components are unresolved in right ascension, to a limit of 6'', and the others have sizes of 6''--8''. The molecular excitation was studied with a series of single-dish measurements, and a new methanol transition, the 10/sub 2/..-->..10/sub 1/(E), was detected. The rotational temperature of the centimeter lines of methanol is approximately 110 K, close to that of the millimeter lines measured by Kutner et al. It is concluded that the methanol masers are being excited by infrared emission from other objects in the vicinity.
24 citations
TL;DR: In this article, a Fabry-Perot spectrometer for airborne observations of astronomical spectral lines has been designed for use in the 50 to 200 μm region of the far-infrared.
Abstract: A Fabry-Perot spectrometer for airborne observations of astronomical spectral lines has been designed for use in the 50 to 200 μm region of the far-infrared. The spectrometer uses a fixed wavelength Fabry-Perot filter cooled to 4.2 K in conjunction with a high order scanning Fabry-Perot at room temperature. This arrangement provides high spectral resolution and also minimizes the thermal background radiation on the detector. The instrument has been successfully used to study all the presently detected fine structure lines between 50 and 120 μm.
18 citations
01 Jan 1980
TL;DR: In this paper, the stars listed by Cocconi and Morrison are referred to in their article, where the 10 light years was erroneously written for 15 light years as noted by Dr. van de Kamp.
Abstract: WHERE the stars listed by Cocconi and Morrison are referred to in our article, 10 light years was erroneously written for 15 light years as noted by Dr. van de Kamp. Even this is not strictly correct, since one of the distances is as large as 16.5 light years. But these differences are not crucial for our purposes.
17 citations
TL;DR: In this paper, the average electron density outside the known ionized clouds and within 30 arcsec of the galactic center is less than 40 per cu cm, and an upper limit is also reported for the forbidden O III 88.4 micron fine-structure line in Sgr A West.
Abstract: The forbidden O III 51.8 micron fine-structure line has been detected in Sgr A West. It appears that the emission arises from the same compact clouds within the central parsec of the Galaxy which are observed in forbidden Ne II. The line intensity is used to derive an effective temperature of 32,000-40,000 K for the radiation field that ionizes the clouds. An upper limit is also reported for the forbidden O III 88.4 micron fine-structure line in Sgr A West. From this upper limit, one can conclude that the average electron density outside the known ionized clouds and within 30 arcsec of the galactic center is less than 40 per cu cm.
10 citations
Journal Article•
1 citations