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OBSERVING SUMMARY Some Highlights of the 1977 Research Program

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OBSERVING SUMMARY Some Highlights of the 1977 Research Program NATIONAL RADIO ASTRONOMY OBSERVATORY 1978 NATIONAL RADIO ASTRONOMY OBSERVATORY 1978 OBSERVING SUMMARY Some Highlights of the 1977 Research Program The construction of the VLA continued on schedule. By the end of the year the array was operating with nine antennas and had a maximum baseline of 10.5 km. The first maser for the range 18.3 to 26.4 GHz was installed and operated at the Cassegrain focus of the 140-foot. System temperatures ranged from 50 K at 20 GHz to 70 K at 22.3 GHz under the best weather conditions. Radio emission from the Wolf-Rayet binary HD 193793 has been detected; these observations offer the possibility of measuring the rate of mass loss from this object. A radio flare of UX Ari was ob¬ served, during which the fractional circular polarization reached 50 percent. A highly variable source was found at galactic longitude 136° and galactic latitude +1°. It has subsequently been identified with an 11th magnitude OB star, and may be a source of y-ray radiation. The 140-foot telescope provided high-sensitivity observations of atomic H which form the basis of a new model of the fundamental distribution of gas in the inner portion of our Galaxy. The model in¬ volves a tilted disk 3 kpc in diameter within which smoothly distributed gas is rotating and expand¬ ing, and accounts in a coherent way for many spectral features previously studied separately and variously identified with bars, spiral arms, or isolated ejecta. The 36-foot telescope was used at 9 mm to detect "dips" in the cosmic microwave background in the direction of three clusters of galaxies. The effect arises because of scattering by the hot gas between the galaxies in the cluster. OBSERVING HOURS TELESCOPE IMPROVEMENTS CONSTRUCTION AND OPERATION <CO UJ I- < 1968 ' ' 1969 ' 1970 ' 1971 ' 1972 ' 1973 ' 1974 ' 1975 ' 1976 ' 1977 ' 1978 ' 1979 ' 1980 ' 1981 ' 1982 ' 1983 ' 1984 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 FISCAL CALENDAR YEAR YEAR Fig. 1. The upper figure shows the year in which existing (black) or planned (shaded) telescope systems are incorporated into the NRAO observing program. The lower figures show the total number of hours of observing time during each year. OBSERVING TIME DISTRIBUTION 300-FOOT INTERFEROMETER 140-FOOT 36-FOOT 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 CALENDAR YEAR ■I PERMANENT STAFF ffift VISITORS M TESTING AND CALIBRATION Fig. 2. These graphs show the number' of hours devoted to calibration and testing and to observing by NRAO permanent staff members and by visitors on each telescope system during the last decade. 36-FOOT RADIO TELESCOPE SUMMARY CALENDAR YEAR ■ OBSERVING EQUIPMENT FAILURE, WEATHER INSTALLATION, MAINTENANCE AND INTERFERENCE AND CALIBRATION Fig. 3. This summary for each quarter of the calendar year shows the per¬ centage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experi¬ ments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. 140-FOOT RADIO TELESCOPE SUMMARY 1968 1972 1973 1976 CALENDAR YEAR OBSERVING EQUIPMENT FAILURE, WEATHER INSTALLATION, MAINTENANCE AND INTERFERENCE AND CALIBRATION Fig. 4. This summary for each quarter of the calendar year shows the per¬ centage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experi¬ ments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. 300 FOOT RADIO TELESCOPE SUMMARY 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 CALENDAR YEAR -OBSERVING - EQUIPMENT FAILURE, WEATHER INSTALLATION, MAINTENANCE AND INTERFERENCE AND CALIBRATION Fig. 5, This summary for each quarter of the calendar year shows the per¬ centage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experi¬ ments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. INTERFEROMETER RADIO TELESCOPE SUMMARY 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 CALENDAR YEAR -OBSERVING ■ EQUIPMENT FAILURE, WEATHER INSTALLATION, MAINTENANCE AND INTERFERENCE AND CALIBRATION Fig. 6. This summary for each quarter of the calendar year shows the per¬ centage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experi¬ ments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. FULL-TIME PERMANENT EMPLOYEES 400 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 19731974 1975 1976 1977 1978 1979 1980 19811982 1983 1984 FISCAL YEAR CALENDAR YEAR Fig. 7. This figure shows the total number of NRAO full-time, permanent employees at the end of each year, projected into the future. NUMBER OF PEOPLE ENGAGED IN RESEARCH AT NRAO 400 350 300 250 200 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 CALENDAR YEAR Fig. 8. This bar chart shows for each calendar year the size of the NRAO permanent research staff and the number of research associates on one or two year appointments. In addition it shows the total number of visitor-users of NRAO telescopes and the number of in¬ stitutions from which the NRAO visitors come. Distribution of Telescope Time by Per Cent 36-ft Interferometer 140-ft 300-ft 1977 Summary Visitors 63% 48% 51% 38% 50% Students 7 12 9 30 15 Permanent Staff 10 15 15 12 13 Research Associates 1 9 2 9 5 Test and Calibrate 4 8 5 1 4 Maintenance and Installation 14 6 17 9 12 Holidays and Unscheduled 10 Distribution of Scheduled Observing Time in Various Research Areas, by Per Cent 36-ft Interferometer 140-ft 300-ft 1977 Summary I. Solar System—Sun, Planets, Satellites, Interplanetary Medium, Astrometry 3% 3% 2% 2% 3% II. Galactic Sources—Continuum Stars, X-ray Sources, HII Regions, Supernova Remnants, etc. 23 13 12 III. Galactic Sources—Line Dust Clouds, HII Regions, IR Sources, Molecular Searches, etc. 52 58 28 IV. Galactic Structure—Line and Continuum Spiral Arms, Halo, Galactic Center, High Velocity Clouds V. Extragalactic Sources—Continuum Normal Galaxies, Radio Galaxies, Quasars, VLB Studies 19 62 18 28 32 VI. Extragalactic Sources—Line Hydrogen, Molecules in Galaxies, Quasar Absorption Studies, etc. 13 48 19 11 INSTITUTIONS FROM WHICH VISITORS CAME TO USE NRAO TELESCOPES DURING 1977 TELESCOPE INSTITUTION 36-ft Interferometer 140-ft 300-ft 1. Aerospace Corp. x x 2. Alabama, U. of x 3. Applied Phys. Inst., Gorky, USSR Acad. Sci. x 4. Arizona, U. of x x x 5. Battelle-Northwest Laboratories x 6. Bell Telephone Labs x 7. Berkeley, U. of California x x x 8. Bologna, U. of Italy x 9. Bonn U., W. Germany x 10. Brandeis U. x 11. British Columbia, U. of Canada x x 12. California Inst, of Tech. x x x x 13. California State, Fullerton x 14. CTIO, Chile x 15. Chalmers Univ. of Tech., Sweden x 16. Chicago, U. of x x 17. CSIRO, Australia x 18. Crimean Astrophysical Obs., USSR Acad. Sci. x 19. DTM, Carnegie x x x 20. Florida, U. of x x x 21. Florida Technological Inst. x 22. Fordham U. x 23. Harvard, Center for Astrophysics x x x 24. Haverford College x x 25. Hawaii, U. of x x 12 TELESCOPE INSTITUTION 36-ft Interferometer 140-ft 300-ft 26. Haystack Research Facility 27. Illinois, U. of x 28. Indiana U. x 29. Inst, for Advanced Study, Princeton X 30. IOTA, Cambridge, England X 31. Inst, for Space Res., Moscow, USSR Acad. Sci. 32. Iowa, U. of 33. Jet Propulsion Lab 34. Jodrell Bank, England 35. Kapteyn Lab., Groningen, Netherlands 36. Kentucky, U. of 37. Kitt Peak National Observatory 38. Leiden Observatory, Netherlands 39. Lockheed Research Lab 40. Los Angeles, U. of California 41. Maryland, U. of x 42. Massachusetts, U. of x 43. Massachusetts Inst, of Tech. x x 44. Max-Planck I. R., Bonn, W. Germany x x 45. Max-Planck I. P. & A., Munich, W. Germany X 46 Minnesota, U. of x 47. Monash U., Australia x 48. NASA-Ames Research Center 49. NASA-Goddard (Greenbelt) x 50. NASA Inst, for Space Studies (NYC) x 51. NASA Marshall Space Flight Center x 52. National Astronomy and Ionosphere Center x 53. National Bureau of Standards X 54. National Geodetic Survey 55. National Research Council, Ottawa, Canada 13 TELESCOPE INSTITUTION 36-ft Interferometer 140-ft 300-ft 56. Naval Research Lab x x x 57. National Science Foundation (DC) x 58. Netherlands Foundation for Radio Astronomy x x 59. Observatoire de Paris, France x 60. Ohio State U. x x 61. Oklahoma, U. of x 62. Pennsylvania, U. of x x x 63. Penn State U. x 64. Pittsburgh, U. of x x x 65. Princeton U. x 66. Purdue U. x 67. Queen Mary College, London, England x 68. Rensselaer Polytechnic Inst. x 69. Rice U. x 70. Rochester, U. of x 71. Santa Cruz, U. of California x x 72. Stanford U. x 73. SUNY, Albany x 74. SUNY, Stony Brook x 75. Sussex, U. of, England x 76. Tata Institute, Bombay, India x 77. Tennessee, U. of x x 78. Texas, U. of x x 79. Toronto, U. of, Canada x x x 80. Torun Obs., Poland x 81. Toyama, U. of, Japan x 82. Tufts U. xx 83.
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