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NATIONAL RADIO ASTRONOMY OBSERVATORY 1973 I- NATIONAL RADIO ASTRONOMY OBSERVATORY HISTORY AND PLANS TABLE OF CONTENTS Pag;e Observing Hours................................. ........................... 1 Observing Time Distribution..........******** *............................. 2 36-foot Radio Telescope Summary................................................. 3 140-foot Radio Telescope Summary.................. .......... ......... 4 300-foot Radio Telescope Summary....................................5 Interferometer Radio Telescope Summary........................................ 6 Full-time Permanent Employees .............************. 7.................7 Number of People Engaged in Research at NRAO...........8.. .......... 8 Visitor Representation by Institution........................ 9 Distribution of Scheduled Telescope Time by Percent .............. 10 Institutions from Which Visitors Came to Use NRAO Telescopes During 1972 ........................................................... 11 Doctoral Theses for Which Major Work Was Done at NRAO....................... 14 NRAO Student Program...* * *.............................................15 NRAO Summer Student Program........,................ ..................... 16 Telescopes and Receiver Systems........................................... 17 NRAO Front-End Boxes.......................... ............................ 18 VLA Performance Data.............,.................................................... 20 VLA Construction Program................. ............................. 22 Millimeter Wave Antenna........ ................................. 23 Observatory Report. ....................... ............................... 26 Staff and Visitor Publications......... **.**** .......................... 32 OBSERVING HOURS VL A --- 36'-fl TELESCOPE IMPROVEMENTS I ~ti~'////////////////lllllllllllll~'~llI Cr) 85 - 3- z I I~'///////////////////////////////////// z 14 0'-- wL I ~'/////////~'///////////////I/////////// Fz 85-2 - I IEi~'//////////////~'/////////////////// 185-7 300 '-- ~ji~'////////////////llllllllllll~"lllll L I 13j~-//////////////////////////////////I _ 1959 '1960 196111962 I 1963 11964 11965 1966 11967 '1968 111969 1970 1 1971 '1972 11973 1974 1975 11976 11977 1978 1979 L 40 30 0 0 0 20 O0 OL 1303 I9(1 V LE' I (U iy rr I IiTe Ilr1 I('4 ftUr1 IJ 1 lyre FISCAL YEAR CALENDAR 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 figure shows the total number of hours of observing time during each year. OBSERVING TIME DISTRIBUTION 300 -FOOT INTERFEROMETER 140-FOOT 36-FOOT 0 0 0 x Cf) ID 0 -I 1965 1966 1967 1968 1969 1970 1971 1972 1966 1967 1968 1969 1970 1971 1972 1968 1969 1970 1971 1972 FISCAL CALENDAR FISCAL CALENDAR CALENDAR YEAR - PERMANENT STAFF VISITORS STESTING 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 each year the telescope has been operative. 36-FOOT RADIO TELESCOPE SUMMARY wz L 0-L CALENDAR YEAR 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 maintenance and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. 140-FOOT RADIO TELESCOPE SUMMARY zF- w C) ELL0 CALENDAR YEAR 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 maintenance and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. 300-FOOT RADIO TELESCOPE SUMMARY F- L .C) LU 0 CALENDAR YEAR 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 maintenance and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. INTERFEROMETER RADIO TELESCOPE SUMMARY 100 80 z 60 wLU w 40 20 0 CALENDAR YEAR 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 maintenance and installation of new experiments, and the percentage of time lost due to equipment failure, bad weather, and radio interference. 6 FULL- TIME PERMANENT EMPLOYEES 80 LL LL I- 60 U) - 40 l-0 IL 0 20 0 0 FISCAL YEAR CALENDAR YEAR 400 _ ___~~___ 300 i BASIC RESEARCH AND TECHNICAL L- ALL OTHER 200 zzD 100 -'l 0 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 FISCAL YEAR CALENDAR YEAR Fig. 7. The lower figure shows the total number of NRAO full-time, permanent employees at the end of each year, projected into the future. The upper figure shows the percentage of these employees each year that are in the basic research staff (lower curve) or who are either research or technical (upper curve). NUMBER OF PEOPLE ENGAGED IN RESEARCH AT NRAO 400 350 NUMBER OF INSTI TUTIONS m:; PERMANENT S TAFF 300 EE' E"E-, El RESEARCH ASSOCIATES lillil VIS/ TORS - - 't,., 250 -- _ '".."- -- ",. .,r cc CWen :3 200 cos ID 2:- . .. "" ""' 150 """'''" "''''' """' ""'''' ""''''' ""' ;t; "" i'"' """' ;r;. 100 ;;. .;t ;; ; .;t..;, 50 ;;; ..s ::-: ::j:::- -- fi. I ::2~i:-i.-.. -~' ' -I"" ' 0 - ---~- 1959 1960 1961 1962 1963 1964 1965 1966 1967 1969 1970 1971I 1972I 1973ll 1974IL 197511 1976 197711 1978ft 1979 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. VISITOR REPRESENTATION BY INSTITUTION Domestic Institutions No. Individuals Dome .stic Institutions N 4o. Individuals 1. Maryland (11) 20 23. Florida (1) 2. M.I.T. (8) 20 24. Hampshire 3. Illinois (6) 10 25. Minnesota (1) 4. Cal Tech (2) 9 26. N.B.S. 5. Harvard (4) 8 27. Stanford (1) 6. Massachusetts (3) 8 28. Unaffiliated 7. Smithsonian Ap. Obs. 7 29. Alabama 8. Virginia (4) 6 30. Brandeis 9. Bell Tel. Labs 5 31. Brookhaven Nat'l Lab 10. NASA-Greenbelt 5 32. Columbia (1) 11. NAIC 5 33. Eastern Mennonite 12. SUNY-Albany (1) 5 34. Haystack Facility 13. Berkeley 4 35. Indiana (I) 14. NASA-Inst. Space Studies 4 36. Iowa State 15.. Princeton (2) 4 37. Lockheed Corp. 16. Aerospace Corp. 3 38. N.S.F. 17. Chicago (2) 3 39. New Mexico State (1) 18. Cornell (1) 3 40. Puerto Rico Univ. 19. J.P.L. 3 41. Rochester 20. N.R.L. 3 42. SUNY-Stony Brook 21. Arizona (2) 2 43. Texas (1) 22. D.T.M.(Carnegie Inst.) 2 44. UCLA Foreign Institutions No. Individuals 1. Max Planck Inst., Germany (1) 9 2. Toronto, Canada (1) 5 3. Chalmers Instit. Tech.,Sweden 4 4. Jodrell Bank, England 3 5. Queens, Canada 3 6. Nat'l. Research Council, Canada 2 7. Queen Mary, England (1) 2 8. Stockholm, Sweden 2 9. Budapest, Hungary (1) 10. Byurakan Ap. Obs.,USSR 11. Pulkovo Obs., USSR 12. Tata Institute, India Note: Numbers of students are shown in parentheses. 9 Distribution of Scheduled Telescope Time By Per Cent 140-ft 300-ft 36-ft Interferometer 1972 Summary Visitors 61% 49% 64% 41% 52.4% Students 11 19 10 12 13.3 Permanent Staff 15 14 16 24 17.7 Research Associates 8 16 4 14 11.4 Test Time 4 1 6 9 5.2 INSTITUTIONS FROM WHICH VISITORS CAME TO USE NPAO TELESCOPES DURING 1972 Telescope Institution 36-foot Interferometer 140-foot 300-foot 1. Aerospace Corp. X X 2. Alabama X 3. Arizona X X 4. Bell Telephone Laboratories X X X 5. Berkeley X X X X 6. Brandeis X 7. Brookhaven National Lab X 8. Budapest, Hungary X 9. Byurakan Ap. Obs., USSR X X X X 10. Calif. Inst. of Tech. X X 11. Chalmers Inst. Tech., Sweden X 12. Chicago X X X X 13. Columbia X X 14. Cornell X X 15. Dept. Terrestr. Magnetism, Carnegie X 16. Eastern Mennonite X 17. Florida X X X 18. Hampshire X X 19. Harvard X X 20. Haystack Facility X 21. Illinois X X X 22. Indiana X X 23. Iowa State X 24. Jet Propulsion Lab X X 25. Jodrell Bank, England X X 11 Telescope Institution 36-foot Interferometer 140-foot 300-foot 26. Lockheed Corp. X 27. Maryland X X X X 28. Massachusetts X X X 29. Mass. Inst. of Tech. X X X 30. Max Planck Inst., Germany X X X 31. Minnesota X X 32. NASA-Goddard (Greenbelt) X X X X 33. NASA-Goddard (NYC) X 34. National Astronomy and Ionosphere Ctr. X X X X 35. National Bureau of Standards X X 36. National Res. Council, Canada X X 37. National Science Foundation X X 38. Naval Research Lab X X X 39. New Mexico State X 40. Princeton X X 414 Puerto Rico, Univ. X 42. Pulkovo Obs., USSR X 43. Queen Marvy, England X 44. Queens, Canada X 45. Rochester X 46. Smithsonian Astrophys. Obs. X X 47. Stanford X 48. Stockholm, Sweden X X 49. SUNY, Albany X X X 50. SUNY, Stony Brook X 12 Telescope Institution 36-foot Interferometer 140-foot 300-foot 51. Tata Institute, India X 52. Texas X 53. Toronto, Canada X X 54. Unaffiliated Scientists X X X 55. UCLA X 56. Virginia X X X X No. Institutions 26 25 39 23 No. Visitors 44 52 83 34 No. Students 10 16 23 14 No. Research Associates; 2 8 7 7 No. Permanent Staff 7 13 10 6 Total Observers : 63 89 123 61 13 DOCTORAL THESES FOR WHICH MAJOR WORK WAS DONE AT NRAO Cr uJ cro z 1969 1970 1971 CALENDAR YEAR Fig. 10. This bar chart shows the number of doctoral dissertations pro- duced each calendar year by Ph.D. students where the major work on the theses was done at the NRAO. 14 NRAO STUDENT PROGRAM wL 50 40 30 20 10 O- 1959 CALENDAR YEAR Fig. 11. This figure shows for each calendar year the number of Ph.D.
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    The Detection of Bright Asymptotic Giant Branch Stars in the Nearby Elliptical Galaxy Maffei 1

    THE DETECTION OF BRIGHT ASYMPTOTIC GIANT BRANCH STARS IN THE NEARBY ELLIPTICAL GALAXY MAFFEI 1 T. J. Davidge 1 Canadian Gemini Office, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 W. Saanich Road, Victoria, British Columbia, Canada V9E 2E7 email: [email protected] Sidney van den Bergh Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 W. Saanich Road, Victoria, British Columbia, Canada V9E 2E7 email: [email protected] ABSTRACT We have used the adaptive optics system on the Canada-France-Hawaii Telescope to study a field 6 arcmin from the center of the heavily obscured elliptical galaxy Maffei 1. Our near diffraction-limited H and K0 images reveal an excess population of objects with respect to a background field, and we conclude that the asymptotic giant branch tip (AGB-tip) in Maffei 1 occurs at K =20 0:25. Assuming that stars at the AGB-tip in Maffei 1 have the ± same intrinsic luminosity as those in the bulge of M31, then the actual distance modulus of Maffei 1 is 28:2 0:3ifAV =5:1, which corresponds to a distance +0:6 ± of 4:4 0:5 Mpc. This is in excellent agreement with the distance estimated from − surface brightness flucuations in the infrared, and confirms that Maffei 1 is too distant to significantly affect the dynamics of the Local Group. Subject headings: galaxies: individual (Maffei 1) – galaxies: distances and redshifts 1Visiting Astronomer, Canada-France-Hawaii Telescope, which is operated by the National Research Council of Canada, the Centre National de le Recherche Scientifique, and the University of Hawaii.