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Science 11 August 1967:
Vol. 157. no. 3789, pp. 676 - 677
DOI: 10.1126/science.157.3789.676
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Articles

Spectral Line Interferometry with Independent Time Standards at Stations Separated by 845 Kilometers

J. M. Moran 1, P. P. Crowther 1, B. F. Burke 2, A. H. Barrett 2, A. E. E. Rogers 3, J. A. Ball 3, J. C. Carter 3, and C. C. Bare 4

1 Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
2 Department of Physics and Research Laboratory of Electronics, Massachusetts Institute of Technology
3 Lincoln Laboratory, Massachusetts Institute of Technology
4 National Radio Astronomy Observatory Green Bank, West Virginia

An upper limit of 0.02 second of arc has been determined for a hydroxyl radical (OH) emission region associated with the radio source W3, with the use of a Michelson interferometer consisting of two radio telescopes 845 kilometers apart. Timing was provided at the stations by independent atomic frequency standards. The 1665-megahertz radiation was translated to video frequency and recorded digitally on magnetic tapes which were later processed by computer, yielding fringe phase and amplitude as a function of frequency over the received bandwidth.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
The Very Long Baseline Array.
K. I. Kellermann and A. R. Thompson (1985)
Science 229, 123-130
   Abstract »    PDF »
Real-Time, Very-Long-Baseline Interferometry Based on the Use of a Communications Satellite.
J. L. YEN, K. I. KELLERMANN, B. RAYHRER, N. W. BROTEN, D. N. FORT, S. H. KNOWLES, W. B. WALTMAN, and G. W. SWENSON JR. (1977)
Science 198, 289-291
   Abstract »    PDF »
Radio Interferometry at One-Thousandth Second of Arc.
M. H. Cohen, D. L. Jauncey, K. I. Kellermann, and B. G. Clark (1968)
Science 162, 88-94
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