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KITT PEAK NATIONAL OBSERVATORY Tucson, Arizona and CERRO TOLOLO INTER-AMERICAN OBSERVATORY La Serena, Chile Operated by the ASSOCIATION OF UNIVERSITIES FOR RESEARCH IN ASTRONOMY, INC under contract with the NATIONAL SCIENCE FOUNDATION QUARTERLY REPORT October-November-December 1970

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  • KITT PEAK NATIONAL OBSERVATORY

    Tucson, Arizona

    and

    CERRO TOLOLO INTER-AMERICAN OBSERVATORY

    La Serena, Chile

    Operated by the

    ASSOCIATION OF UNIVERSITIES FOR RESEARCH IN ASTRONOMY, INC

    under contract with the

    NATIONAL SCIENCE FOUNDATION

    QUARTERLY REPORT

    October-November-December

    1970

  • KITT PEAK NATIONAL OBSERVATORY

    SCIENTIFIC STAFF ACTIVITIES

    Dr. H. A. Abt helped to install and align the 60-inch coude-mirrors and coude" spectrograph optics at Cerro Tololo in Septemberand October. He used the spectrograph for 4 nights, making observations for the determination of radial velocities of standard starsand of visual binaries.

    At the December annual meeting of the American Association forthe Advancement of Science in Chicago, Abt, as Chairman of Section D(Astronomy) during 1970, acted as overall chairman of the one-daysymposium on "Teaching Astronomy in the 70's", and also attended theCouncil Meeting. On December 6, he attended the Council Meeting ofthe 133rd Meeting of the American Astronomical Society in Tampa todiscuss arrangements for a possible ownership change for the Astrophysioal Journal.

    Dr. T. D. Kinman and Mr. D. E. Trumbo visited the WestinghouseTube Division, Elmira, New York, on October 27 to discuss the SECVidicon system that is being acquired for use in the development of

    for the 150-inch telescope. This system, ordered ii;epted subject to minor modifications and will

    future.

    > i u i V.UU Jjr -> ov...i v,.

    instrumentation f

    January, 1970, wabe deli vered in t

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    he near

    The Stellar Subcommittee of the Scientific Committee of the AURABoard met in Tucson on October 22. Dr. George Wallerstein, Chairman,and Drs. Arne Slettebak, Don Osterbrock, and Gerry Neugebauer had invited Drs. Nick Woolf and John Gaustad as consultants. In addition,Drs. Hiltner, Mohler, and Mayall attended, as did members of theStellar Division staff. Topics for discussion ranged from staff research and instrumentation development to policies for the overallutilization of the Observatory's facilities.

    An informal conference on late-type stars, hosted by Drs. H. M.Dyck and G. W. Lockwood, was held at the Tucson headquarters on October 27-28. Recent findings were discussed and papers were given byparticipants who are conducting research in the fields of infraredand microwave astronomy, model atmospheres and abundances, conventional and image-tube spectroscopy, near-infrared photometry, and polar-imetry. The conference proceedings will be printed by the photo-offset process in the near future as an original KPNO publication.

    Drs. Kenneth A. Dick, D. M. Hunten, and Darrell F. Strobel ,Planetary Sciences Division, attended the meeting of the AmericanGeophysical Union held in San Francisco, December 7-10, 1970, Strobel

  • contributed a paper entitled, "The F2 Layer at Middle Latitudes."

    Drs. J. W. Harvey and A, K. Pierce attended the joint meeting ofthe Solar Physics Division of the American Astronomical Society andthe American Institute of Aeronautics and Astronautics during November 17-19 at Huntsville, Alabama. Harvey gave a review paper onsolar magnetic fields, summarizing the work at Kitt Peak and the presentations at the IAU Symposium No. 43 on "Solar Magnetic Fields."On November 16, Pierce met in Huntsville with the advisory group forthe University of Colorado experiment on 0S0-1

    CONFERENCE ON PLANETARY ATMOSPHERES

    The Fifth Arizona Conference on Planetary Atmospheres will beheld at the Hilton Inn in Tucson during March 8-10, 1971, sponsoredby the Planetary Sciences Division of KPNO. The subject this yearwill be "Aeronomy of COo Atmospheres." The emphasis will be on thestability of C02 atmospheres in the presence of ultraviolet radiationAlthough the Conference will be primarily about the atmospheres^ofMars and Venus, relevant aeronomical studies on CO2atmosphere will also be considered.

    in the Earth's

    Results of the Mariner and Venera experiments indicate that C02is essentially undissociated in the upper atmospheres of Mars andVenus. At present, there exists no satisfactory photochemical modelto explain the rapid recombination of the products of C02 photolysisThe Conference will focus on this central problem of CO2 photochemistry and hopefully stimulate research effort toward its solution.

    The purpose of the Fifth Arizona Conference is to increasecommunication among aeronomers, chemists, and planetary physicists.A substantial number of chemists have indicated that they will beattending the meetings. As in previous years, attendance is byinvitation only.

    PERSONNEL NOTES FROM THE SCIENTIFIC DIVISIONS

    Consultants

    Dr. Ron Giovanelli was at KPNO from October 23 through December31 as a consultant to the Solar Division. He is Chief of the Division, CSIRO, National Standards Laboratory, Division of Physics,Sydney , Australi a.

    2-

  • KITT PEAK WEATHER

    October

    Precipitation 0.33 inchin 3 days

    Snow

    TemperatureExtreme High 70°FExtreme Low 28

    Mean High 62Mean Low 4 2

    November

    0,11 inch

    in 2 days

    71°F32

    59

    41

    December

    1.23 i nches

    in 5 days

    1 .25 i nches

    in 2 days

    67°F22

    49

    34

    PUBLIC VISITORS

    Visitors received at Kitt Peak during October, November, andDecember numbered 3,719, 4,119, and 3,172, respectively, for athree-month total of 11,010. The total number of visitors for thecalendar year 1970 was 47, 314.

    INSTRUMENTATION AND RESEARCH PROGRAMS

    Stellar Division

    Replacement of thesive preparations by Laoptical system was plac1970. Only two nightstion, The lightweightby Frank Stuart and MelCER-VIT primary that isradially by a mercury tsecondary mirror of CERnew system, the total mprimary mirror was lighoriginal, solid blank wand cell about 820 pounnew system was done byCal iform' a , and by itsa Cassegrain with an F/

    lesoopIan B i

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    CorporatiDivision,

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    Optical shop tests of the mirrors at Costa Mesa were monitoredby Norman Cole, and further optical tests were made by Drs. Hoag andDyck after installation of the mirrors in the telescope. Hartmann

  • plates acquired by these observers have been measured and evaluatedby Jorge Simmons. Qualitative and quantitative tests indicate thatthe new system is as good as can reasonably be expected for a configuration having an F/2 primary. It was specified that 80% of the lightin an image be concentrated in a circle one second of arc in diameter, and the tests indicate tnat this condition has been met.

    The changeover has resulted in greatly improved optical performance ,thereby making the telescope more suitable for sky-limitedphotometry, as well as for other work at a scale similar to that ofthe 84-inch telescope. The telescope has primarily been used forphotometry, including the infrared, and for polarimetry. In principle, however, any of the KPNO F/13.5 instrumentation can be used withthis reflector. Torque motor drives are being developed in order toimprove tracking and pointing control.

    , M. Dyck afor use in

    i tt Peak.

    50-inch re

    d the offse

    ins trument

    tailed d e s i

    , 1970, andis a sky-c

    iversity ofram of the

    counters a

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    the radiat

    usly. Theemploying aa piane norters a fixe

    etector. T

    al piane , rnch telesco

    tor wi th a

    0 to 25 Hz

    ri ous pi acebS element

    apphi re fi edetectors a

    h Dr. Frank

    er so that

    ng1e night.

    Infrared Photometer (Han experimental photometerbeen put into service at Kphotometer attached to thethe PbS detector system antion was done in the KPNOcarried out much of the debeen in use since November

    promising. The photometerpie to one built at the UnGillette The optical diagThe incoming beam first ena high percentage of the rbut transmits about 40% ofand measurement simultaneoan offset guiding featurely ±2 inches of travel infleeted energy next encounmirror, and finally, the dthe beam 1.5 mm in the foe

    seconds of arc at the 50-icontrolled by a dc servomocontinuously variable fromzer, can be inserted in vaare two detectors: 1) a Pplaced directly behind a sgermanium bolometer, TheLaboratories, Inc. (througchangeable on the photomet20u can be covered in a si

    nd G. W„ Lockwood): Recently,the region lu

  • Fig. 1 Dyck-Lockwood infraredphotometer attached to the 50-inch reflector.

    FIXED MIRR0R--"7

    /COOLED FOCAL

    PLANE APERTURE

    _^PACE-CHOPPING I"\ MIRRORIN ONE I// OFTWOBI-STABLEl' POSITIONS

    SOLD SURFACE MIRROR

    '(PARTIALLY TRANSPARENTTO VISIBLE LIGHT)

    -.TRANSMITTED VISIBLE LIGHT

    AUXILLIARY FOCAL PLANE

    "FOR OFFSET GUIDING

    Fig. 2 Optical diagram of theDyck-Lockwood infrared photometer.

    Harvard scanner; Dr. John Danziger, Nathaniel Hazen, and Stephen Diamond, Harvard University, spent some time at the Observatory duringthis report period in the final development of a 2-channel , Wampler-type scanner. Two of these instruments have been built by the SolarSatellite Project at the Harvard College Observatory: one for KittPeak and the other for Cerro Tololo. Initial tests have shown that theperformance of the finished instrument will be as expected, but someminor difficulties remain in the operation of the cold boxes. Two operational modes now exist for the instrument on Kitt Peak; a test boxcan be used to program wavelength selection and data output to a dua -channel, pulse-counting system, or similiar functions can be controlled

  • by D, E. Trumbo's "Telcom I" computer system. Operational tests arecontinuing and it is anticipated that the instrument will be available soon for routine use.

    Visitor Use of Stellar Telescopes: In the following listing of visitors and their research programs, the first number refers to thenumber of nights scheduled, the figure in parentheses notes the actual hours of observation, and the last figure indicates the telescopeby aperture in inches:

    K. Batishko and F. Roach, Battelle Memorial Institute, Richland,Washington: Diffuse galactic light, 9(20)16.

    M. Breger, State University of New York, Stony Brook: Pre-mainsequence contraction and pulsation in NGC 2264, 14(92)36.

    F. Chromey, Harvard College Observatory: Photometric standardsystems, 16(66)16

    A. Cowley, University of Michigan: Spectroscopic investigation ofsome peculiar binaries, 4(44)84,

    J. Cuffey, New Mexico State University: UBV standards in openclusters , 5(56)50.

    I. J. Danziger, Harvard College Observatory; Photometry and dynamicsof the nuclei of galaxies and scanner tests, 2(13)84, 4(11)36,

    I. J, Danziger, Harvard College Observatory, and E. Becklin and J.Frogel , California Institute of Technology: Infrared photometryof the nuclei of galaxies, 4(17)84,

    J. Drilling, Louisiana State University: Four-color photometry ofearly-type stars, 10(56)50,

    S. Faber, Harvard College Observatory: Photometric observations ofmultiple galaxies, 6(53)36, 7(73)16,

    A. Feinstein, Observatorio Astronomico, La Plata, Argentina: Ha3 and y measures of Be stars and of some metallic-line stars,3(17)16,

    K. Ford and V, Rubin, Carnegie Institution of Washington: Highdispersion spectra of the nuclei of galaxies, 5(51)84.

    P. Hodge and R. Schwarz, University of Washington: Integratedphotometry of extragal actic stellar associations, 4(11)36,

    R. Humphreys, University of Arizona: Spectral classification ofstars in Cas 0B8 and NGC 663, 8(65)16.

  • M. Jennings, University of Arizona: Infrared polarimetry of NGC3034 and related objects, 3(13)50.

    R. Koch, University of Pennsylvania: Photographic search forclose binaries in NGC 2264, 5(27)36.

    A. Landolt, Louisiana State University: UBV faint standards,7(67)36, 3(4)16.

    T. Lutz, Washington State University: Spectroscopy and UBV photometry of selected visual binary systems, 7(69)36, 2(17)16.

    E. Olson, University of Illinois: Spectrophotometry of eclipsingbinaries, 5(46)84.

    B. Peery, Indiana University: High-resolution spectra of cool-element stars, 3(34)84.

    J. Percy, University of Toronto: Photometry of variables, 7(49)16.

    M. Perinotto, University of California, Los Angeles: Spectrophotometry studies of the infrared spectrum of planetary nebulae,3(23)84.

    C. Perry, Louisiana State University: uvby and H3 photometry ofNGC 1039 and 2169, 6(40)36, 7(47)16.

    P. Pesch, Warner and Swasey Observatory: MK classification andradial velocity determinations of faint stars and UBV photometry of Pleiades flare stars, 6(66)84, 5(8)50, 17(130)36.

    A. G. D. Philip and L. Relyea, Dudley Observatory: High galacticlatitude A stars and horizontal branch stars, 5(35)36, 4(40)16

    P. Phillips and D.Gillman, Cornell University: Infrared spectroscopy in the 20u region, 7(38)36.

    S. Plagemann, Institute for Theoretical Astronomy, Cambridge, England: Power spectrum analysis of certain celestial objects,3(6)36, 2(0)16.

    P. Rigterink, University of Pennsylvania: A study of the disturbances in close binary systems, 14(86)16,

    H. Rood and G. Chincarini, Wesleyan University: Kinematics ofthe cluster around NGC 541 and the Perseus cluster, 4(44)84.

    E. Schmidt, University of Arizona: High-dispersion spectralstudies of classical cepheids, 4(36)84.

    C.-Y. Shao, Harvard College Observatory: UBV photometry of planetary nuclei , 6(44 )36.

  • M. Smith, University of Arizona: Line-width study of M stars andphotometry of A stars, 2(25)84, 1(12)3d , 4(28)16.

    W. Stein, F. Gillett, W. Forrest, and R. Gehrz, University of California, San Diego: Infrared photometry, 15(147)50.

    S. and K. Strom, State University of New York, Stony Brook: Pre-mainsequence A-F stars in NGC 2264 and infrared photometry, 3(35)84,6(16)50.

    S. Tapia, University of Arizona: UBV photoelectric photometry ofthe flare star EV Lacertae, 3(2b)1b.

    C. Vesley, R. Sather, and L. Dunlap, University of Arizona: Light-curves of asteroids, 3(35)16.

    K. Voelcker, Heidelberg Observatory, Germany: Photoelectric ooserva-tions of extremely red stars in Cygnus, 2U(151)a0.

    A. Wawrukiewicz, Western Kentucky University: Photometry of M stars,9(81 )16.

    E. Weis, University of Illinois: Rotational velocities in closevisual binaries, b(34)84.

    J. Winzer, University of Toronto: Photoelectric photometry of APstars, 14(b8)lb.

    A. Witt, University of Toledo: UBV photometry of central stars inselected areas, 5(24)84, 3(9)16.

    J. Wray and G. Corso, Northwestern University and Kendall College:Detection of Wolf-Rayet stars, 3(3u)84.

    A. Young, B. Nelson, F. Vaughn, and G. Grupsmith, San Diego StateCollege: Velocity curve of BD+lb°Dlo3, 3(27)84, 3(22)bU.

    D. Zipoy, University of Maryland: Near infrared photometry of youngcl us te rs , b (1 5)3b .

    Total visitor use of stellar telescopes:

    61(549)84 67(469)50 97(650)36 118(721)16

  • 84-inch

    5 0 - i n c h

    No. 1 36-inch

    No. 2 36-inch

    No. 3 16-inch

    No. 4 16-inch

    Summary of Teles cope Use

    October

    31(298)

    24(205)

    28(240)

    24(182)

    16(119)

    23(179)

    November

    29(312)

    26(243)

    21(207)

    29(272)

    15(116)

    26(231)

    December

    26(174)

    15(103)

    20(132)

    15(118)

    7(36)

    15(120)

    The 50-inch telescope was down for two nights in November for installation of the new CER-VIT optics.

    Solar Division (A. K. Pierce)

    During one of the regular monthly maintenance shutdowns, November3, the cable on the hoist of the #2 mirror of the east auxiliarysystem was run out of the drum. This failure released the carriage,which went down the inclined track about 100 feet and impacted the#2 main carriage. This #2 mirror is a 36-inch Kanigen-coated aluminum mirror of 135-foot focal length, and the impact broke it loosefrom its simple support. It then fell about 15 feet onto the baseof the #2 main carriage. The mirror face is marred with a number of1/4-inch diameter dents, but its figure has not yet been checked.

    The impact also caused the #2 63-inch main mirror to jump about2 inches and, as it settled back into its support band, the clipsspalled a 6-inch round chip from one edge. The figure of the mirrorwas in no way changed and the chipped area does not affect the image,because the mirror can be oriented so that there is no light loss tothe spectrographs—the gratings are overfilled in normal operation.

    Three CER-VIT mirror blanks have been purchased to replace allthe optics of tne main beam. The present quartz mirrors of the mainoptical system often give 10-cm astigmatism, which gives a circleof confusion of 5/6 mm, or about 2 seconds of arc; we would hope withthe new optics to have images of 1/4 to 1/3 second of arc resolution.Also, we plan to use a slice from the 42-in en diameter and 24-inchthick core of the CTI0 158-inch CER-VIT blank to replace the east #2metal mirror. This material has worked so well in the west auxiliarysystem in giving high quality images (Fig. 3) that we have put replacement optics at the top of our priority list. Figure 3 shows typicalprominence spectra obtained as part of W. Livingston's program ofmeasuring solar rotation from radial velocities of prominences.

    -9

  • Ca K3933 Ha6562 W Limb PromWL - 30957 + 2498 film 0902 12 March 1970

    Fig. 3 Typical prominence spectra obtained as part of Livingston'sprogram of measuring solar rotation from radial velocities of prominences.

    Visitor Use of the McMath Solar Telescope: The following observersconducted various research programs during the three months reported.

    Dr. Claude Arpigny, Institut d'Astrophysi que , Coi nt-0ugre*e , Belgium:Photoelectric scanning of integrated solar spectrum.

    Dr. R. G. Giovanelli, CSIRO, Sydney, Australia: Consultant to theSolar Division on magnetic field problems, solar physics, and jointprograms with the Solar Physics Observatory at Culgoora, New SouthWales, Australia.

    Karen Angle Harvey, Lockheed Solar Observatory: Solar magnetic fields.

    Dr. Robert Howard, Hale Observatories: Joint program with Jack Harveyon short-period oscillations in solar spectrum lines.

    Dr. J. P. Mutschlecner, Indiana University: Determination of abundancesfor rare elements in the solar atmosphere.

    Dr. Pierre J. Swings, Hale Observatories and Institut d'Astrophysique,Cointe-0ugr£e, Belgium: Forbidden lines [Si I] in the photosphericspectrum.

    Lawrence Testerman (graduate student), Kansas State University: Production of synthetic star spectra.

    Dr. Alan Title, Harvard College Observatory: Test equipment to be usedon coming observing run.

    Dr. G. Walker, Dr. J. Aumand, B. Goldberg, B. Isherwood, and D. Wright,The University of British Columbia, Vancouver, Canada: Photoelectricdetection and measurement of weak stellar magnetic fields

    10-

  • KPNO PUBLICATIONS

    The following papers by staff members and visiting scientists(including graduate students) were accepted for publication between1 October and 31 December 1970. Complete publication information isgi ven when avai1able.

    Abt, H. A. and Golson, J. C. 1970,"Photometry and Radial Velocities of W Serpentis,"Inform. Bull. So. Hem. } No. 16, po. 3b-3b.

    Abt, H. A., Muncaster, G. W., and Thompson, L. A. 1970,"Rotational Velocities in the Orion Nebula Cluster"

    Astron. J. _7_5 , 1095.

    Bel ton, M. J. S., McElroy, M. B.s and Price, M. J."The Atmosphere of Uranus"As trophys. J.

    Burbidge, E. Margaret and Lynds , C. Roger 1970,"The Absorption Lines of Quasi-Stel1ar Objects,"Sci. Amer. _223, 22.

    Danziger. I. J."A Short-Period Variable in the Galactic Cluster NGC 7789"Vubl. Astron. Soc. Vac.

    Dyck, H. M. and Sandford, M. T., II"Multicolor Polarimetry of some Mira Variables"Astron. J.

    Feinstein, A. and Marraco, H. G."The Open Cluster NGC 4609 Behind the Coal Sack"Vubl. Astron. Soc. Vac.

    Ford, W. K. , Jr., Rubin, V. C.s and Roberts, M. S,"A Comparison of 21-cm Radial Velocities and Optical RadialVelocities of Galaxies"

    Astron. J.

    Hall, D. S. and Weedman, S. L."UBV Photometry of Eclipsing Binaries with Visual Companions"Vubl. Astron. Soc. Vac.

    Hill, G. and Barnes, J. V."A Spectroscopic and Photometric Investigation of NGC 7243"Astron. J.

    Jennings, M. C. and Dyck, H. M."The Wilson-Bappu Technique Applied to Moderate DispersionSpectrograms"Astron. J.

    1 1

  • McClure, R. D. and Crawford, D. L."The Density Distribution, Color Excess, and Metallicity ofK-Giants at the North Galactic Pole"Astron. J.

    McConnell, J. C. and McElroy, M. B. 1970,"Excitation Processes for Martian Dayglow"J. Geophys. Res. _75 , 7290.

    Mook, D. E., Hiltner, W. A., and Lynds , C. R. 1970,"Spectroscopic Observations of Scorpius X-l"Astrophys. J. 163, L69.

    Parkinson, T. D."A Phase and Amplitude Study of Auroral Pulsations"Vianet. Space Sci.

    Parkinson, T. D. and Zipf, E. C. 0"The Auroral Intensity Ratio of [0I]6300 A and [0I]5577 A"Vianet. Space Sci.

    Smith, M. A."Microturbulence and Abundances in Am Stars: Inferences Concern'

    ing Metal 1i ci sm"Astron. Astrophys.

    Smith, M. A."Equivalent Width Data for Several Am Stars in Clusters andComparison Standards"Astron. Astrophys. Suppl. Ser.

    Strobel, D. F. and Weber, E. J. 1970,"Properties of the Flow Equations of a Multicomponent Plasmawi th Source Terms ,"Eos, _5J_, 796.

    Traub, W. A. and Roesler, F. L."The Abundance of Lithium in Sunspots"Astrophys. J.

    Wal1erstein, G."Observations of Emission-Line Stars in the Near Infra-Red"Vroc. Astron. Soc. Vac.

    Wyckoff, S. and Wehinger, P."Spectral Changes in V Cassiopeiae"Vroc. Astron. Soc. Vac.

    12'

  • RESEARCH SUPPORT DIVISION

    The ISO- tnct Telescope Building and Dome

    During this report period, the building and dome that will housethe 150-inch telescope (and its support facilities) on Kitt Peak werecompleted. The M, M. Sundt Construction Company, Tucson, was the primecontractor, under a contract let October 14, 1967. AURA personnelbegan the site preparation work in April, 1967 and Sundt began workat the site in March, 1968. Most of their work was finished by midyear 1970. The architects were Skidmore, Owings, and Merrill, Chicago,the firm also engaged for the McMath Solar Telescope on Kitt Peak.

    The structure is on the summit ridge of Kittthe mountain top), with the ground floo»~ at 6830The main observing floor is about 100 feet abovetop of the dome is 80 feet higher.

    Peak (north end offeet above sea levelthe ground and the

    The distinctive appearance of the building is the result of using10 tubular frame modules, called "hexahedrons", to form the outersupport structure (Fig. 4), Each hexahedron is about 100 feet long,30 feet wide, and weighs about 35 tons. They were fabricated in onepiece in Phoenix, Arizona, trucked to the site, and installed at therate of one a day.

    The 500-ton, 105-foot diameter dome rotates on 32 trucks that travel on a circular railroad track. The dome structure is a double

    shell with an outer skin of 1/4-inch steel plate and an inner "wall"made of 26,600 square feet of insulating panel liners. Outside airvents upward through the shell. A 50-ton and a 5-ton travellingcrane are located at the top of the dome. The shutter opening is anup-and-over type, but with the two lowest sections moving downward.The shutter is also insulated and vented. Figure 5 shows the externalappearance of the completed building and dome.

    The telescope Itself will be mounted on a free-standing concretepier that is completely independent of the building and dome surrounding it, to ensure that no vibrations will be transmitted to the telescope. The pier is 37 feet in diameter, 92 feet high, and has 18-inchthick reinforced concrete walls. It is offset 3 1/2 feet from thebuilding's center line. The concrete was placed in July, 1968 in a72-hour continuous pouring operation. Photographs showing this processand other construction phases were published in Sky and TelescopeVol, 38, No, 5 (November), 1969,

    The building comprises approximately 30,000 square feet of floorspace and contains photographic darkrooms, electronics laboratories,a mechanical and electrical shop, offices, and a small kitchen, aswell as the observing floor, coudd spectrograph rooms, and storageareas. Detailed floor plans are available upon request. Figures 6-9show interior views of the building as it currently looks,,

    13'

  • Several features are included to accommodate public visitors.A special elevator will transport them from the ground-floor levelto the 90-foot level, where they can view the telescope during theday from a "visitors gallery." At this height, they will be ableto see the rest of the mountain and much of southern Arizona froman enclosed walk-way that encircles the building.

    Installation of the telescope is scheduled to begin late inthe first quarter of 1971, but the telescope is not expected to bein test operation until 1972.

    The building and dome for the 150-inch telescope on Cerro Tololoare nearing completion and should be finished by mid-1971. The rotating dome is identical to the one at Kitt Peak, and, while the building structure is different, the same systems were used for insulation,heating, cooling, and the other design aspects.

    Fig. 4 Hexahedrons forming theouter support structure.

    •14-

    Fig. 5 External appearancethe completed facility.

    of

  • Fig. 6 The main floor level of the 150-inch telescope building,in a view to the northwest, showing the main hatch, through whichall the telescope parts and the mirror will be hoisted. Thevisitors' gallery is also visible.

    15-

  • mr-i ipi in n

    Fig. 7 A view to the southwest at the main floor level. Thetelescope mounting will occupy most of the area between thesloping walls. The control room is behind the windows on the"balcony."

    -16-

  • Fig. 8 The main console in the control room.

    17-

  • r*—m t

    Fig. 9 The largest room in the building, a general purpose labo^ratory space, located two levels below the main floor.

    18-

  • Advanced Programs & Technology

    During December, 1970, the Advanced Programs & Technology (APT)group was established and charged to work on advanced-level technicalproblems related to telescope and instrumentation projects. Thisgroup will recognize and respond to problems during early projectstages; some of their work done during the previous three months issummarized below.

    ISO-inch telescopes projects: 1) Hartmann tests of the KPNO primary mirror were continued with a newly completed 440-hole screen,Wavefront contour diagrams and energy distribution charts were derivedto show if some improvement is still needed, 2) Tests of the primarymirror support air regulators '-/ere conducted and have led to minorrevisions. 3) A special lubricant was selected for the declinationbearings; the choice was severely limited by such factors as high contact stresses, slow speed, and inability to clean the bearings periodically, 4) Inspection and preliminary approval of the main drive bull-gears and gearboxes were completed for both KPNO and CTIO telescopes.5) Final bidding specifications for mirror handling equipment were completed; the principal item is the handling carriage for moving largeparts, such as the primary mirror cell,. 6) A method for substantiallyincreasing stepping-motor speed capability has been devised, intended tosolve a reaction-impact problem found with the present instrument rotator drive. The new method will also be useful in the automaticguider drives, 7) Preliminary configuration work was begun on a TVimage tube - faint star photometer for D^s, T. D„ Kinman and H. M„ Dyck.8) Control consoles built by the United Power Company were checked outand approved. Work continued on specification and design of computersystem peripheral hardware and related logic circuitry, 9) Progressalso was made on the "Data Link" system that will transmit controland data information to and from the various telescope positions, control consoles, and the computer,

    proposal.

    1) An ootical configurationGeneral: 1) An ootical configuration is beingFourier transform spectrometer at the direction of2) A preliminary engineering study of possibledone for the PIan"

    completed for theDr. J, W, Brault.

    mount styles is beingietary Sciences

    Of particularstyles presented by Drs.sub-committee in October

    recommend optimum mirrorMcMath Solar Telescope

    inch so1

    work is

    iences Division coude laboratory telescopeinterest are the Alt-Alt and the Az-Alt

    D . :I. H u n t e n and T, Parkinson to the d iv is

    des ien

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    initiated to

    nd optimum mirror mountings for new CER-VIT mirrors in theSolar Telescope,, 4) Testi no of the control panel for the 82-lar mirror support system has been completed, and installationscheduled for January, 1971.

    Mechanical & Electrical Engineering

    General:

    been made and

    Parts for modifying the 36-inch grinding machine have1 be installed in January, 1971. This work will

    improve the machine's effectiveness for more critical usage, including

    19-

  • grinding of the secondary mirrors for the 150-inch telescope.

    Stellar Division Support: A description of the replacement of theoptics in the 50-inch telescope is given in the RESEARCH AND INSTRUMENTATION section of this report. Engineering design continued on themounts and building modifications of the 84-inch telescope externalcoude" feed.

    CTIO Support: \Ar. R. L. Stevens made an inspection trip toChile to check the progress of electrical installation projects atLa Serena and Cerro Tololo, including the 150-inch telescope building.His report indicated substantial progress and good workmanship. Theinstallation of La Serena's new 300 KVA main electrical service center,new office, and housing power distribution transformers and feeders isnearing completion..

    On Cerro Tololo, the communications trench and cover are completeand delivery of the cable tray and fittings is awaited.

    The components necessary to change the 60-inch telescope secondaryfocus to a 2-speed operation are ready for shipment to CTIO.

    ISO-inch telescope projects : The following maintenance manualsfor the 150-inch telescopes were published and distributed in theirprelimi nary fo rm:

    Vol. 8 The f/12-f/30 Mirror Flip Assembly

    Vol. 9 The Secondary Mirror Assemblies (f/8 Mirror Assembly)

    Design-Drafting

    During this report period, the following projects have been completed: 1) Electronic drives (right ascension and declination) forthe 50-inch telescope have had all the aesign changes made necessaryfor installation, 2) Detailing of the Cassegrain instrument rotatorfor the 150-inch telescope was completed. 3) Design and detailing ofthe 3,34m planetary spectrometer were completed, and many of the subassemblies, fabricated elsewhere, were received. 4) The solar tele-

    lUr Lilt: idu- lliun lc i CiLupc was luiiiu ic lcu. o / uco lyn

    the 3,34m planetary spectrometer were completed, andassemblies, fabricated elsewhere, were received. 4)scope infra-red spectrograph slit area mechanisms werfabrication is proceeding.scope infra-red spcuuyiufabrication is proceeding.

    All drawing documentation in the Researcn Support Division is beingconverted to a micro-film system. The micro-film chips are mounted instandard IBM cards and accompanied with pertinent key-punched data,which allows the system to interface with computer printout and sortingfunctions. The master card file system will be in the engineering department at Tucson headquarters, with duplicate files at Kitt Peak andCTIO.

    •20-

  • Space Engineering Laboratories

    During the past three months, major effort was concentrated onAerobee KP 3.32, which is due to fly in February, 1971, for Dr. L.V. Wallace, KPNO, To study Venus in ultraviolet light, the instrument for this flight will be an Ebert-Fastie spectrophotometer designed to cover the spectral interval of 1215A to 1216.2A with aresolution of about 0.165A. Its design and construction are beingdone at KPNO.

    Work also proceeded on several other Aerobee rocket flights; theprincipal investigators and their programs are indicated in parenthesesKP 3.37 (Donald Morton, Princeton University, observations of the interstellar medium in the ultraviolet); KP 3.36 (A. L. Broadfoot, KPNO,airglow, visible); KP 3.29 (L. V. Wallace, KPNO, Jupiter, ultraviolet);KP 3.35 (Richard L, Blake, University of Chicago, Sun, x-ray); andKP 3.38 (Robert Novick, Columbia University, SCO X-l, x-ray).

    AURA Engineering Technical Reports

    The following three technical reports were issued during the pastquarter. Copies are available upon request.

    No. 29 Miller, R. H., "A Fringe Detector for Use with MichelsonStellar Interferometers"

    No. 31 Miller, R. H., "A Phenomenological Representation for Seeing"

    No. 32 Pearson, E, T., "Thermo-Elastic, Infinitesimal Deflectionand Stress Analysis for a Homogeneous, Isotropic Body.Part II: Governing Relations for Rectangular CartesianCoordinates and the Rectangular Parallelepiped Body"

    Addendum: The following report was inadvertantly omitted from theprevious Quarterly Report,

    No. 22 Vokac, P. R., "Conceptual Design of a Shaft Encoder Interface"

    ADMINISTRATIVE DIVISION

    AURA Meetings

    The Subcommittees of the Scientific Committee and the Chile Committee of AURA, Inc., met in Tucson from October 20 through 23, 1970.Reports on research activities were presented by staff members of theSolar, Stellar and Planetary Sciences Divisions of KPNO, and by Dr.John Graham, CTIO. The FY 1973 budgets and five-year plans for FY

    -21

  • 1973 through FY 1977 were discussed.

    vember meeting of the Executive Committee of AURA, Inc.n Chile. Board members and Mr. Daniel Hunt, Head, NSFNational Centers and Facilities Operations, and Dr. RobertHead, NSF Astronomy Section, arrived in Santiago on Novem-n interview was arranged by Dr. Blanco with the Foreign Min-Clodomiro Almeyda, which was attended by Blanco, Professorsand H. Moreno of the University of Chile, Drs. Edmondson, Mr. Miller, and AURA's Chilean Counsel, Sr. 0. Kolbach., November 17, Dr. Blanco, Professor Anguita,Dr. Fleischer, Dr. May all and Sr. Kolbach metducat ion, Sr. Mario Astorga while the rest ofto La Serena. All visitors were accommodatedno in La Serena.

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    The officers of AURA, Inc., met at La Serena headquarters November18, and later that afternoon the group travelled to Cerro Tololo,where housing was provided in the astronomers' dormitory and the newly-completed technicians' dormitory. That evening, Dr. Barry H. Laskerdemonstrated the NOVA computer, and Dr. P. Osmer showed the visitorsobjects in the Southern Hemisphere skies with the 60-inch telescope.

    The Executive Committee meeting was held in the 150-inch telescopebuilding on Cerro Tololo. Among actions taken at the meeting wereappointment of architects for the Cerro Tololo technicians' dormitoryaddition, La Serena laundry facility, and La Serena library addition,and approval of recommended signature authorizations on the Bancode Chile. Dr, Blanco reported on a preliminary proposal (to be givenfurther study) received from the State University of New York concerning their joint acquisition with the University of California of a60-inch infrared telescope, to be located possibly on Cerro Tololo.He also reported that the government of Chile would be issuing a commemorative postage stamp depicting CTIO.

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  • Chile, attended the meeting as an invited guest, and expressed thehope for continued cooperation between the two organizations,

    J. M. Miller reported that the "AURA Construction Company"would be dissolved at the earliest possible date, and the ExecutiveCommittee expressed its appreciation to Mr. S, R. Hurdle, Construction Superintendent, for a job well done.

    After the Executive Committee meeting, the group returned to LaSerena, and on November 20, visits were made to ESO on La Silla, andto the CARSO installation on Cerro Las Companas, A LAN-Chile charterflight, which circled Cerro Tololo twice for the benefit of the passengers, took the group to Santiago on Saturday, November 21, wherethey were guests of the Observatorio Astronomico Nacional at CerroCalan for a delicious "asado" in the beautiful gardens of the Observatory .

    The Organization Committee of AURA, Inc., met on December 16 atthe O'Hare International Airport in Chicago. It reviewed activitiesof the Administrative and Research Support Divisions, and discussedthe FY 1973 budget and long-range projections for both Observatories,prior to their scheduled presentation at the Board of Directors'meeting on January 21, 1971.

    annual

    NSF Meeting

    On November 3 and 4, J. M. Miller, Associate Director-Administration and F. G. Taylor, Personnel Officer, attended a meeting at theNational Science Foundation in Washington, D. C, with representativesof the other National Centers to discuss the Atomic Energy Commissionuse of the Battelle Memorial Institute study of scientific salariesfor forecasting scientific salary budgets.

    Operations Department

    A new fire alarm system has been installed at the Tucson headquarters building. It is designed to operate manually as well asautomatically in the event of fire or overhead fire sprinkler discharge. The circuits are tied into the Central Alarm of Tucson andthe Tucson Fire Department to insure 24-hour protection and immediateresponse in event of an emergency.

    PersonneI

    Mr. B. E. Powell joined the Observatory staff in the capacity ofContract Administrator and Negotiator on October 19, 1970.

    23-

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  • CERRO TOLOLO INTER-AMERICAN OBSERVATORY

    Drs. John Graham and William Kunkel attended the American Astronomical Society meeting, December 6-9, at Tampa, Florida. Grahamcontributed a paper entitled "The Field RR Lyrae Stars in the LargeMagellanic Clouds" and Kunkel presented one entitled "A Search forPeriodic Phenomena in the Activity of Solar Neighborhood Flare Stars

    Special Visitors

    On November 19, Professors I. Tajanov and R. Estrognov of theDepartment of History of Lomonozov University, Moscow, U.S.S.R.,visited Cerro Tololo.

    Messrs. J. Jones, M. Rhoades, and R. Stevens of the KPNO ResearchSupport Division were at CTIO from November 31 to December 10.

    Long-term visitor Mr. William Stonacker, University of Arizona,completed a record-length observing run at CTIO on December 20. Heused a 16-inch telescope for seven months to carry out a program ofbasic multicolor photometry for all Southern Hemisphere stars brighterthan visual magnitude 5.0.

    Instrumentation and Research Programs

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    vations of the Large Magel-sclosed exceptionally violenthese are the most pronouncedregions observed by means ofations of sixty-one otherud indicate that these regionsotions. Of the nebulae ob-han 30 Doradus, exceptionalina Nebula and in Ml 7. As a

    cy radial velocities are beinging the rotation-curve of the

    Drs. Barry Mstar R 548 to be

    Lasker and James E. Hesser found the white dwarf

    a periodic variable with a dominant period of 212.864

    -25-

  • 0.031 seconds and a secondary period of 273,0 ± 0.6 seconds. Theamplitude of the dominant variation is 0.01 mag and of the secondary, between 0.01 and 0.001 mag. Except for DQ Her and the pulsars,R 548 appears to be the shortest period variable star with a well-defined light curve so far discovered.

    The analysis of the observational data on R 548 by Lasker andHesser was carried out with the newly installed IBM 1130 computer.This facility was put into operation in September, 1970, under thesupervision of Kunkel.

    On November 5, 1970, Graham discovered a nova in the Large Magellanic Cloud, The visual magnitude of the nova at the time of discovery was between 12 and 13, This discovery was made during a routine,long-term3 nova-search program on the Magellanic Clouds that is beingcarried out at CTIO nit'r. the Curtis Schmidt telescope of the University of Michigan, The program was initiated at the suggestion of Dr.A.D*. Thackeray-, Radcliffe Observatory, Pretoria, South Africa, andhad been started only two weeks prior to the discovery. Prompt announcement of this finding permitted confirming observations at otherobservatories. For example, at ES0 on La Silla, spectroscopic andphotometric observations were made as early as November 7, 1970,

    The aluminizing tank for the primary mirror of the 150-inch telescope received extensive rust damage in transit to Chile. Mr, FrankGolden has undertaken the required repairs before the tank is storedto await the arrival of the 150-inch telescope.

    CTIO 60-inch Coude Spectrograph (H- A. Abt): In September and October,the 60-inch coudd telescope optics and spectrograph optics were installed

    obtai nedand aligned on Cerro Tololo and the first stellar spectra were obt(Fig, 10), This spectrograph is now available to visiting astrono mers

    The spectrograph room is lined with aluminum sheeting that coversa 6-inch thick layer of styrofoam. No additional temperature controlis planned, although air filtering may be installed later. Supportedon the telescope pier, the spectrograph baseframe is horizontal, withthe optical plane five feet above the floor. Light coming down thepolar axis from the four telescope mirrors is reflected by a fithstationary flat to the slit (Fig 11). Currently available at the slit

    •26-

  • HUP ™aP?SPWit

    Fig. 10 A fifteen-fold enlargement of aof i1 Sco (F2 la). 0The pair of iron arcseparation of 0.30 A or 33 u.

    60-inch coude spectrum1i nes marked has a

    are iron arc, hollow cathode, and neon comparison sources; order-blocking filters; and a digital telescope drive control in bothcoordi nates.

    Collimator mirrors for 9- and 12.5-inch beams are installed. ABausch & Lomb 8xl0-inch double-diamond grating of 600 grooves/mm iscurrently being used. Three schmidt cameras on a square, rotating beam(Fig. 12) are designed, two age built, and one is in use; it gives areciprocal dispersion of 9.0 A/mm in the second order blue-violet.When put into use, other cameras will give reciprocal dispersions of4.5 and 18 A/mm with the same grating.

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    ary, 1966; the design specificationsng by Dwight Ludden. Carl Carlsong the spectrograph; the result is annown major difficulties. In April,oiler & Chivens for the final de-The mechanical parts were completed

    ed in Pasadena by Larry Ott and Abt,The spectrograph was assembled inrge Briones, Patrick Osmer, and Abt.done that the assembly of parts,ng beam with its complex bearing and

    Meanwhile, work on the optics continued at the KPNO optical shopin Tucson. Harold Wirth figured the coud£ secondary, Ivan Lawrence,the #3 and #4 flats, and Edwin Mason, the two collimating mirrors.The superb optics for the 36-inch focal-length schmidt camera were

    -27

  • Fig. 11 An observer looking through the guiding eyepiece (hidden)at the 60-inch telescope coudd spectrograph slit; he holds thehand control paddle. The coude" console is to the left and the digital drive control box is in front of him. The #5 flat is on thevertical column; it reflects stellar light coming down the polaraxis (upper right) to the slit. (Photograph by Tony Parada)

    28-

  • Fig. 12 Inside the 60-inch coude" spectrograph room. The grating(far left) reflects a spectrum through an 18-inch diameter corrector plate (left of the observer) to the f/4 camera mirror (in thebox to the right with the cover hanging down). The observer holdsa plateholder that attaches to the mounting in front of him. Thesquare beam can rotate to bring other cameras to the optical axis.

    -29-

  • completed in nine months by Lynn Hepburn; their resolution is better than 5u , so that the photographic plate grain is the limitingfactor. The optics were installed by Abt, Osmer, Ludden, andBriones, with much help from others on Cerro Tololo. It was challenging to align the components, especially those involving adjustments for translation in three coordinates and rotation about three

    axis. The coudd console, made in Tucson, was badly damaged in shipping. Electrical wiring of the spectrograph was done by Sergio Cath-alifaud, Leandro Caimanque, German Pinochet, and others.

    Theospectrograph speed is such that in average seeing a spectrumof 9.0 A/mm dispersion and 0.6 mm wide for a star of B = 5.0 mag canbe obtained in 15 minutes on 11 a-0 plates developed in D76. Sevenspectra of two velocity standards (HR 188, 1829) were measured bySaul Levy; the instrumental corrections are -0.2 and +l.lkm/sec, respectively. The mean scatter is, respectively, ±0.38 and ±0.15 km/secp.e. per plate, or 0.6u and 0.2u.

    A contract extension recently negotiated with Boiler & Chivenswill include the remaining mechanical parts. An integrating exposuremeter is being built in the Tucson electronics laboratory. The #5 flathas an alternative position that sends stellar light to another roomcontaining a photoelectric scanning spectrograph.

    Visiting Observers

    In the following listing of observers and their programs, thefirst figure indicates the number of nights scheduled, the figurein parentheses is the hours of actual observing time logged, whilethe last figure denotes the aperture of the telescope in inches.

    H. Abt, Kitt Peakof southern B

    8(52)60.

    National Observatory, Tucson: Rotational velocitiesA stars and classification of southern A stars,

    L. Aller, University of California, Los Angeles; S. Czyzak, Ohio StateUniversity, Columbus; H. Epps , University of California, LosAngeles: Spectrophotometry of selected stars and nebulae in theMagellanic Clouds and n Carinae, 4(33)60, 10(87)3o, 3(26)24/36

    L. Cathey, Lick Observatory, Santa Cruz, California:of giant and subgiant stars in globular clusters,1(3)24.

    UBV photometry4(33)60, 1(2)36,

    S. Demers, Laurentian University, Sudbury, Ontario, Canada: a) Asearch for variable stars in Fornax, b) Magnitude and colorcurves of Population II Cepheids in the Large Magellanic Cloud,2(17)60, 10(59)24/36.

    F. Forbes, University of Arizona, Tucsonselected Southern Hemisphere objectsnight observations 6(53)60, 6(40)36.

    30-

    Infrared polarization ofdaytime observations 6(16)60,

  • P. Lucke, University of Washington, Seattle: Photometry of clustersand stellar associations in the Large Magellanic Cloud, 5(41)60,4(28)24/36, 3(24)24.

    E. Mendoza, Universidad Nacional de Mexico: Infrared photometry(JHKL) of objects in the Large Magellanic Cloud, 12(95)60.

    B. O'Leary and D. Ward, Cornell University, Ithaca, New York: Photometry of Venus and Mercury, daytime observations, 26(182)16,night observations, 18(69)16.

    A G. D. Philip, Dudley Observatory, Albany, New York: Horizontalbranch stars, 4(34)36, 6(44)24/36.

    W. Sargent and G. Neugebauer, California Institute of Technology,Pasadena: Infrared photometry of the Magellanic Clouds, nCarinae, and of selected objects, 4(32)60, 6(55)36.

    A. Slettebak, Perkins Observatory, Delaware, Ohio: a) Brightsouthern rotational velocity standard stars, b) Early-typestars in the south galactic pole region, 4(32)60.

    J. Stock, University of Chile, Santiago, E. Figueroa, J. Hesser, B.Lasker, W. Kunkel, CTIO: Simultaneous spectroscopic and photometric observations of SX Phoenicis,4(24)60 , 4(21 )36 , 4(10)#1 164(10)#2 16.

    W. Stonacker, University of Arizona, Tucson: Multicolor basic photometry for stars brighter than 5.0 magnitude, 66(431)16.

    D. Weedman, Dyer Observatory, Vanderbilt University, Nashville,Tennessee, and M. Smith, CTIO: Fabry-Perot interferometry ofthe 30 Doradus nebula, 11(95)36.

    R. Williamon, University of Florida, Gainesville: Photoelectricphotometry of the eclipsing variables BV 421 (U2 Oct) and TWCeti , 12(64)16.

    Universtiy of Michigan Program: 18(21)24/36,

    Staff Observers

    J. Graham, CTIO: RR Lyrae stars in the Magellanic Clouds, uvbyphotometry of high latitude blue stars, Magellanic Cloud novasearch, 7(46)60, 2(15)36, 7(48)24/36.

    J. Hesser, CTIO: a) UBV photometry ofsouthern galactic clusters,b) Photoelectric monitoring of degenerate stars, c) Red andinfra-red photography of the Magellanic Clouds, 6(53)60,17(103)36, 10(60)24/36.

    31

  • W. Kunkel, CTIO: Monitoring of flare star, UV Ceti , 2(17)24/36,2(16)24.

    B. Lasker, CTIO: Spectroscopy of white dwarfs; Short-period variable stars, 4(25)60, 4(35)36.

    P. Osmer, CTIO: a) Four-color and H(3 photometry of Sanduleak SMCstars, b) Image-tube spectra of Magellanic Cloud stars in thenear infrared. c) HB and infrared photometry of MagellanicCloud stars, 11(88)60, 6(45)36, 3(24)24.

    M. Smith, CTIO: a) Tests of image tube spectrograph, b) Directphotography of extragalactic radio sources, c)Interferometricobservations of the Large Magellanic Cloud, 5(31)60, 19(137)36.

    CTIO PUBLICATIONS

    The following papers were published or accepted for publicationduring October, November, and December 1970:

    Brandt, J. C, Stecher, T. P., Crawford, D. L., and Maran, S. P."The GUM Nebula-Fossi1 StrtimgrenSphere of the Vela X Supernova"Astrophys. J.

    Chambli ss, C. R."A New Photoelectric Investigation of the Eclipsing Binary RRCentauri"

    Astron. J.

    Chambli ss, C. R."Photoelectric Photometry of the Dwarf Cepheid HD 199757"Astrophys. J.

    Chiu, H.-Y., Lynds, C. R., and Maran, S. P. 1970,"On the Optical Identification of the Vela Pulsar"Astrophys. J. 162, L99.

    Hesser, J. E. and Lasker, B. M."High Frequency Oscillations. V. Power Spectra for the CentralStars of Planetary Nebulae"Astrophys. J.

    Hesser, J. E. and Hartwick, F. D. A."The Intermediate Age Galactic Cluster NGC 2660"Proc. Astron. Soc. Pac.

    Humphreys , R. M."Streaming Motions in the Carina-Centaurus Region"Astrophys. J.

    Landolt, A. U."UBV Photometry of the Southern Cepheids I Carinae, AG Crucis,and ST Puppis"Publ. Astron. Soc. Pac.

    32-

  • Lasker, B. M. and Hesser, J. E."High Frequency Stellar Oscillations. VI. R548--A Periodically-Variable White Dwarf"Astrophys. J.

    Lasker, B. M. and Hesser, J. E."High Frequency Stel1ar Osci11ations. V. Power Spectra for theCentral Stars of Planetary Nebulae"Astrophys. J.

    O'Leary, B. and Jackel , L."The 1969 Opposition Effect of Mars Full Disk, Syrtis Majorand Arabia"

    Icarus

    CTIO Documentary Film

    A photographic crew consisting of John Lutnes, supervisor, KPNOphotographic laboratory staff members Thomas Eglin and Peter Ratkevichand Robert Anderson of California began filming in Chile on October 26for the second in the KPNO-produced documentary film series, andreturned to the U.S. on November 17, with over 9,000 feet of exposedfilm,

    Admini

    Effective September 30, Mr. Rolf Korp resigned from his positionas Administrative Manager-CTIO; he held this position since May 13,1963. Mr. Korp and his family are now residing in Santiago.

    The following CTIO staff members returned to the U.S. during thelast quarter after completion of their duties in Chile:

    N. LePore, Assistant Mountain Superintendent, October 1W. Johnson, carpenter foreman, 150-inch building project, October

    15S. Hurdle, 150-inch building construction supervisor, December 10C. Lelo, chief instrument maker-CTIO, December 10

    On October 15, Mr. Paul Qui 11 en, accompanied by his wife Diana,arrived in Chile to assume the position of electrician at CTIO.

    -33-

  • Construction

    The office addition to the La Serena headquarters building hadthe interior partitions finished, the electrical, heating, and plumbing networks installed, and the roof completed during the reportperiod (Fig. 13).

    Fig. 13 Construction of the CTIO office building addition in LaSerena, Chile.

    The technicians' dormitory on Cerro Tololo was first occupiedby 36 CTIO employees on November 30, 1970. Two wings and the central hall of this building are now completed (Figs. 14, 15).

    •34-

  • Fig. 14 Exterior view of the technicians' dormitory on Cerro Tololo

    Fig. 15 The central lounge area in the technicians' dormitory

    -35-

  • The final phase of the 150-inch telescope building constructionwas initiated, namely work on interior carpentry details and finishing. It is planned that this phase of the project will be completedas a CTIO activity in collaboration with the engineering group of theKPNO Research Support Division. A commendable job was done by StuartHurdle who supervised the construction of the building from its initialphases in October, 1967, until his return to the U.S. on December 10,1970. During their years in Chile, Mr. Hurdle and his wife Elna mademany friends and they will be very much missed.

    Library

    During the report period, three shipments of library material consisting of journals, publications, and 91 new books were received fromKPNO for the La Serena and Cerro Tololo libraries. In addition, 90bound volumes were returned by the bindery in Santiago.

    Cerro Tololo Weather

    October

    TemperatureMaximum 22?8CMinimum 1?1

    Maximum Wind

    Velocity 74 mph

    Observational

    Nights 20

    lovember

    23?9C

    4?4

    53 mph

    29

    December

    24?4C

    8?9

    41 mph

    31

    Drought conditions continue to affect the northern part of Chilefrom the southern limits of the province of Coquimbo northward. Duringthe three months reported, traces of drizzle were felt twice in LaSerena, but there was no precipitation at all on Cerro Tololo.

    Public Visitors

    Public visitors to Cerro Tololo numbered 310, 378, and 353 duringOctober, November, and December, respectively, for a total of 1,041.Visitors for the entire calendar year of 1970 numbered 3,659.

    36-

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    First Prize

    WINNERS OF THE CTIO PHOTOGRAPHY CONTEST

  • Second Prize

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    Honorable Mention

    38-

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    Honorable Mention

    -39-

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