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  • NATIONAL RADIO ASTRONOMY OBSERVATORY

    Observing Summary - 1979 Statistics

    February 1980

  • NATIONAL RADIO ASTRONOMY OBSERVATORY

    Observing Summary - 1979 Statistics

    February 1980

  • Some Highlights of the 1979 Research Program

    By the end of the year observations had been made at the VLA site with an array of 19 antennas. The longest astronomically usable baseline was approximately 24 km between antennas at 17.2 km on the southwest arm and at 10.5 km on the east arm. The first VLA scientific spectral line research was completed during the last quarter of the year.

    As part of an extensive study of the dynamical properties of spiral galaxies of all luminosities along the Hubble sequence, the 300-ft telescope was used to survey a sample of high luminosity spirals having optical rotation curves which do not decrease at large distances from the nucleus. The search was carried out in an effort to determine if neutral hydrogen exists at radial distances of two to three times the optical image and if so at what rotational velocities. The presence of significant mass located at large nuclear distances is important for an under standing of galaxy formation and evolution.

    Up to seven antennas have been used in conjunction with the 140-ft telescope in a VLBI experiment designed to investigate the detailed structure of the peculiar galactic source SS 433. Elongated structure on the order of an arcsecond in size is apparently roughly aligned with the bulges in the surrounding HII region, W50. The alignment suggests that the two objects are related and pose interesting parallels with extragalactic jet radio sources which are many orders of magni tude larger in size and mass.

    The VLA was used in a series of experiments to map the radio brightness distribution of the re gion around the double quasar 0957-561. The asymmetric radio picture is more complicated than the simple two-point optical one of two quasars with identical redshifts. Ultimately, it is hoped to be able to adequately test the hypothesis that these objects are gravitational lens images of a single object. Further monitoring for variability is, however, necessary.

    Studies of the distribution of 12C0 and -^CO in ^^ Galaxy have continued in order to probe in detail the association between the atomic and molecular gas distributions. Molecular cloud sizes, masses, typical separations, and radial distributions are under investigation. ^CO molecular features near the galactic center region were further studied in order to pursue several predictions of the model which confines the inner-galaxy gas to a smooth, rotating and expanding, tilted disk.

  • Observing Hours 40

    30 est. est. est. est. est.

    o o o

    x 20

    o in

    est.

    ;&-ggj 'M8&

    1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

    Calendar Year

    1300-Foot 140-Foot ^M36-Foot WJ\ Interferometer ilil/Z./?

    Fig. 1. This figure shows the hours scheduled for observing on each telescope during the last decade.

  • Distribution of Scheduled Observing Time

    36-Foot 140-Foot 300-Foot

    o o o

    1970 71 72 73 74 75 76 77 78 79 1970 71 72 73 74 75 76 77 78 79 1970 71 72 73 74 75 76 77 78 79

    Calendar Year Calendar Year Calendar Year

    \NRA0 Staff I Visitors I Testing and Calibration

    Fig. 2. These graphs show the number of hours scheduled for calibration and tests and for observing by the NRAO staff and by visitors on each telescope system during the last decade.

  • 36-Foot Radio Telescope Summary 100

    80

    60

    Q_ 40

    20-

    - A A 4 ^ A r A r A / A /" ^ /"

    - i /

    ^* A / /**

    \ A S \ A r ^ ^ 1 / y \l / \ [I 1 ^

    V f \

    W ^

    \ A,

    /

    - A ti / V / \ W V A I V A

    fl

    -

    - / \l t j A u \ V \ ,.. y / V \ /^ \ / j \ \ A \ / A y 1 V \ I / t . J. / \) ** V / / f V J v.- > / > 5/ -*>. -*> 1 V, rfr 1 T 7 .y \ J / ._' t J \.

    Calendar Year

    Observing Installation, Maintenance and Calibration Equipment Failure, Weather and Interference

    Fig. 3. This summary for each quarter of the calendar year shows the percentage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. The telescope is removed from service for a period of 4-6 weeks each summer, during the wet season. This period is used for maintenance and upgrading of the instrument.

  • 140-Foot Radio Telescope Summary 100

    80

    r 60

    40

    20

    >N V, ^v r ^_ ^ ^_ / N \/ /^ S v < / A /" A s /- -" s~ ^

    - > A / A /

    f V

    V A s/ V -

    -

    ^ lO" f

    -

    - j \ / \ A V A

    -

    v.- S

    /N CM

    V- / V ^

    .. ^ V

    - ^\

    V- / v ^7 V s V '"v. . -**d - -

    1970 1971 ' 1972 ' 1973 ' 1974 1975

    Calendar Year

    1976 1977 1978 1979

    Observing Installation, Maintenance and Calibration Equipment Failure, Weather and Interference

    Fig. 4. This summary for each quarter of the calendar year shows the percentage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. Major improvements to the telescope system include: 1972 - new control computer and resetting surface; 1974 - installation of the cassegrain system; 1977 - data processing computer and installation of the maser cassegrain system; and 1978 - tests of the deformable subreflector.

  • 300-Foot Radio Telescope Summary 100

    80

    60

    CD

    ^ 40

    20

    0

    \ f v ^ , / /^ ^ - ^- ^v i r -v S^ ^ - ^ - \^ - "N V /^ **s A V - A ^ \ V \ r s/ \ V /

    - I - - / /

    A \

    -

    -y I / A V - - J \ v < ^ X *.. - -.-''~" A \^ ss ^ - /s -i^ Calendar Year

    Installation, Maintenance and Calibration Equipment Failure, Weather and Interference Observing

    Fig. 5. This summary for each quarter of the calendar year shows the percentage of time the telescope was scheduled for observing, for routine calibration, maintenance, and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. The telescope was resurfaced in 1970 and painted in 1973.

  • Very Large Array Telescope Summary

    During 1979 the principal activity at the VLA site in New Mexico continued to be the construc tion and installation of the array. With the completed portion of the array the limited program of tests, calibrations, and observations that was begun in previous years was greatly expanded, using up to 19 antennas. Observing frequencies included 1400-1700 MHz, 5000 MHz, 15 GHz, and 22 GHz.

    Throughout 1979, approximately 1209 hours were scheduled for test and calibration, and fully 2464 additional hours were scheduled for research programs involving 159 observers. A total of 136 visitors and students used the VLA during 1979.

  • Full-Time Permanent Employees

    e

    450

    400

    350

    300

    250

    200

    150

    100

    50

    \\/LA Construction

    | Research and Operations

    1111111111111111111111111 1957 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 \ ., /\ /

    Fiscal Year Calendar Year

    Fig. 6. 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 Observing With NRAO Telescopes

    1959 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85

    Calendar Year

    Fig. 7. This bar chart shows for each calendar year the number of NRAO permanent research staff and the number of research associates who use the telescopes. In addition, it shows the total number of visitor-users of NRAO telescopes and the number of institutions from which the NRAO visitors come.

  • Distribution of Telescope Time by Per Cent (Excluding VLA)

    Visitors

    Students

    Permanent Staff

    Research Associates

    Test and Calibrate

    Maintenance and Installation

    Holidays and Unscheduled

    36-Foot 140-Foot 300-Foot 1979 Summary

    56% 48% 39% 48%

    8 7 21 12

    11 15 17 14

    0 16 8 8

    7 4 6 6

    17 9 7 11

    10

  • Institutions from which Visitors Came to Use NRAO Telescopes during 1979

    Telescope

    Institution 36-ft 140-ft 300-ft VLA

    1. Aerospace Corporation 2. American Science and Engineering 3. Arcetri Astrophysical Observatory, Italy 4. Arizona, U. of 5. Arizona State U.

    6. Bell Telephone Laboratories 7. Berkeley, U. of California 8. Bo chum, U. of, W. Germany 9. Bowling Green State U.

    10. Brandeis U.

    x x

    11. British Columbia, U. of, Canada 12. California Inst, of Technology 13. Carter Obs., New Zealand 14. Chalmers U. of Tech., Sweden 15. Chicago, U. of

    x x

    16. Columbia U. 17. Copernicus, U. of, Poland 18. Cornell U. 19. CSIRO, Australia 20. Davis, U. of California

    x x X

    X X

    21. DTM, Carnegie 22. ESO, Switzerland 23. Florida, U. of 24. Fordham U. 25. George Mason U.

    11

  • Institution 36-ft

    Telescope

    140-ft 300-ft VLA

    26. Hale Obs. 27. Harvard, Center for Astrophysics 28. Hawaii, U. of 29. Haystack Research Facility 30. Helsinki, U. of, Finland

    31. Herzberg Inst., Canada 32. Illinois, U. of 33. Institute for Advanced Study, Princeton 34. Institute for Space Research, Moscow, USSR 35. Institute of Astronomy, Cambridge, UK

    36. Iowa, U. of 37. Jet Propulsion Laboratory 38. JILA, Boulder 39. Jodrell Bank, England 40. Kapteyn Lab, Groningen, Netherlands

    x x

    41. Kentucky, U. of 42. Kitt Peak National Observatory 43. Laboratorio di Radio Astronomy, Bologna, Italy 44. Lick Observatory 45. Leiden Observatory, Netherlands

    46. Lockheed Research Lab 47. Manhattan College 48. Maryland, U. of 49. Massachusetts, U. of 50. Massachusetts Inst, of Tech.

    x x X

    12

  • Institution 36-ft

    Telescope

    140-ft 300-ft VLA

    51. Max-Planck I.R., Bonn, W. Germany 52. Mexico, Institute of Astronomy 53. Milano, U. of, Italy 54. Minnesota, U. of 55. NASA-Goddard (Greenbelt)

    x x

    X X

    X X

    X X

    56. NASA-Inst. for Space Studies (NYC) 57. National Astronomy and Ionosphere Center 58. National Bureau of Standards 59. National Geodetic Survey 60. Naval Research Lab

    x

    x

    X

    X X X X X

    61. National Science Foundation (D.C.) 62. Netherlands Foundation for Radio Astronomy 63. Nevada - Las Vegas, U. of 64. New Mexico I.M.T. 65. North Carolina, U. of

    x x X

    66. Northwestern U. 67. Pennsylvania, U. of 68. Penn State U. 69. Pittsburgh, U. of 70. Queen's U., Canada

    71. Rensselaer Polytechnic Inst. 72. Rice U. 73. San Diego, U. of California 74. Smithsonian Astrophysical Obs. 75. SUNY, Stony Brook

    x x

    13

  • Institution

    76. Stockholm, U. of, Sweden 77. Tennessee, U. of 78. Texas, U. of 79. Toronto, U. of, Canada 80. Tufts U.

    81. U.S. Naval Obs. 82. Virginia, U. of 83. Virginia Polytechnic Inst, and SU 84. Washington, U. of 85. Wisconsin, U. of

    36-ft

    x x X

    Telescope

    140-ft 300-ft

    x x X X X

    X X X X

    X

    X

    VLA

    X X X X X

    No. Institutions

    No. Visitors

    No. Students

    No. Research Associates

    No. Permanent Staff

    Total Observers

    37

    108

    53

    184

    19

    58

    46

    80 142 32 119

    17 20 14 17

    1 4 4 7

    159

    All told, 343 visitors, including 59 students, from 85 institutions,

    14

  • Doctoral Theses for Which Major Work Was Done at NRAO

    1962 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 Calendar Year

    Fig. 8. This bar chart shows the number of doctoral dissertations produced each calendar year by Ph.D. students where the major work on the theses was done at the NRAO.

    15

  • NRAO Student Program

    100

    80

    60

    40

    20

    | Undergraduate

    WCo-op ^ Summer Graduate

    MPh.D.

    2Z

    est. est. est. est. est. est.

    1959 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83

    Calendar Year

    Fig. 9. This figure shows for each calendar year the number of Ph.D. students (salaried and non-salaried), co-op students, and summer undergraduate and graduate students who observed or worked at the NRAO during that year.

    84 85

    16

  • NRAO Front-End Box Status

    TECHNICAL DATA SHEET

    NOVEMBER 1979 io. 12 PAGE 1 OF 4

    Applicable Telescope

    Frequency (MHz)

    Amplifier Type

    System Temperature

    (Kelvin)

    3 dB Bandwidth

    (MHz)

    Feed Type Polarization

    Calibration Value Switching System Remarks

    Person In

    Charge

    300-ft Fixed on Traveling Feed

    140-ft CUp-On

    50-80

    Transistor

    *450 K - * 500 K with Dicke switch.

    5 10% Bandwidth. Tunable Crossed-

    Simultaneous 0*, 45*, 90', 135* Linear, RCP and LCP. Removable quad hybrid at feed for circular.

    Adjustable 30 K to 30 000 K.

    Removable diode Dicke switch.

    Designed for pulsar, continuum, and line work. 110-500 MHz feeds can be manually rotated 45* and 90* for polarization work. UsaUe with 4- channel multi-bandwidth receiver and all NRAO line receivers. About 2 hours to change Dicke switch and feed hybrid. Frequency switching not availaUe.

    Behrens/ Atkins

    110-250 * 200 K - 260 K with Dicke switch.

    140 Broadband Crossed- Dlpole.

    Adjustable 8 K to 8000 K.

    250-500

    > 320 K. * 200 K with removaUe 330-450 MHz amplifiers. Additional 50 K with Dicke switch.

    250

    Broadband Crossed- Dipole.

    Adjustable 1.5 K to 1500 K.

    300-ft Fixed on Traveling Feed

    140-ft

    515-610 Tunable Paramp Ch X

    > 150 20 to 40 Broadband Crossed- Dipole

    Single linear; circular with removable quad hybrid. Dual polarization at 610 MHz.

    5 K or 50 K

    Frequency switching. RemovaUe Dicke switch. Adds ^ 40 K to T .

    sys

    Traveling feed box for 300-ft. Can be used on 140- ft. No box rotation. Multiple polarization with IF polarizer on 300-ft at 610 MHz. About 2 hours to change hybrid and Dicke switch. Feed can be manu ally rotated 45* and 90* on lx. Narrowband feed required above 670 MHz for best efficiency.

    Brundage

    610-740 Tunable Paramp Ch Y

    300-ft Fixed on Traveling Feed

    140-ft

    740-880 Tunable Paramp Ch X

    i 150 20 to 40 Broadband Crossed- Dipole.

    Single linear; circular with removable quad hybrid. Dual polarization at 835 MHz.

    5 K or 50 K

    Frequency switching. Removable Dicke switch. Adds . 40 K to T

    sys

    Traveling feed box for 300-ft. Can be used on 140-ft. No box rotation. Multiple polariza tion with IF polarizer on 300-ft at 835 MHz. About 2 hours to change hybrid and Dicke switch. Feed can be manually rotated 45* and 90* on box.

    Brundage

    830-1000 Tunable Paramp Ch Y

    300/140-ft 1000- 1450 Dual Channel

    Cooled Upconverter

    45 to 70 200 Single Beam Scalar

    Orth. Linear 3.4 K Frequency switching. Part of 4.5-5.1 GHz receiver listed below. Feed change required to go to 6 cm.

    Coe

    17

  • TECHNICAL DATA SHEET NOVEMBER 1979

    No. 12 PAGE 2 OF H

    ApplicaUe Telescope

    Frequency (MHz)

    Amplifier Type

    System Temperature

    (Kelvin)

    3dB Bandwidth

    (MHz)

    Feed Type

    Polarization Calibration

    Value Switching System Remarks Person

    in Charge

    140/300-ft 1410 Dual Channel

    Cooled Paramp

    50 25 Scalar Orth. Linear 4 K Frequency switching. Can be remotely tuned anywhere in frequency range 1375-1435 MHz. Two channels can be used simultaneously at different frequencies. Six polarizations are...

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