+  280-420 GHz Single Ended Rx (‘Barney’)
        Jacob Kooi, Chip Sumner, Riley Ceria,   12th of March 2006

  +  A CSO Submillimeter Active Optics System
        Leong, M. M.   2005, in
USNC/URSI National Radio Science Meeting Proceedings  (Boulder, CO)

Thermal Effect on Pointing of the CSO telescope on a Nasmyth Focus Using the SHARCII at 350 micron
        Shinnaga, H.  22nd of November  2004

    Pointing data taken at  lambda 350micron (850GHz) using SHARCII during 31 August  -- 04 October 2004 were thoroughly examined and analyzed to improve the pointing of the telescope on a Nasmyth focus. The results clearly show that there is a temperature dependency on the pointing (~1 arcsecond shift per +1 degC change for both FAZO/FZAO axes over a temperature range of  - 2  --  +5 degC).  This technical memorandum summarizes the results and suggests that it would be useful to take the temperature into account for the pointing model of the telescope in future.

+ Controlling a telescope chopping secondary mirror assembly using a signal deconvolution technique
        Houde, M., Holt, C. L., Yoshida, H., Nelson, P.M., August 2003, in Review of Scientific Instruments vol 74, 3802

We describe a technique for improving the response of a telescope chopping secondary mirror assembly by using a signal processing method mased on the Lucy deconvolution technique.  This technique is general and could be used for any systems, liniar or nonlinear, where the transfer function(s) can be measured with sufficient precision.  We demonstrate how the method was implemented and show results obtained at the Caltech Submillimeter Observatory using different chop throw amplitudes and frequencies.  No intervention from the telescope user is needed basides the selection of the chop throw amplitude and frequency.  All calculations are done automatically once the appropriate command is issued from the user inferface of the observatory's main computer. 

+ Dish Surface Optimization System, Surface Correction on a 10.4-meter Leighton Primary Mirror
        Leong, M., Houde, M., Peng, R., Yoshida, H., Chamberlin, R., Phillips, T.G., 2003, in AMOS Technical Conference Proceedings, ed. P. Kevin and J. Africano (Kihei, HI)

A Dish Surface Optimization System (DSOS) is in operation at the CSO on Mauna Kea, Hawaii.  The DSOS corrects the 10.4-meter primary surface for imperfections and deformations due to gravitational forces at the dish moves in elevation.  Controlled heating and cooling of the steel rod standoffs that interface the dish panels to its backing structure applies the corrections.  An improvement of twice the aperture efficiency is desired at 350 micron.  This implies that the integration time could be reduced by a factor of four, and six times more new deepfield objects could be detected. 

+ Temperature Measurement on the Leighton Telescope: Surface Memo No. 2

        Chamberlin, R.A. 7th of January 2003

+ A method for implementing the CSO surface correction hardware: Memo No.1 

        The CSO staff,  18th of October 2002

+ Measurement, Modeling, and Adjustment of the 10.4 m Diameter Leighton Telescope
        Woody, R.,  Serabyn, E., Schinckel, A., 1998, in Advanced Technology MMW, Radio, and Terahertz Telescopes, SPIE Proceedings Series vol. 3357, ed: Phillips, T.G., SPIE-The international Society for Optical Engineering, Bellingham

+ Pointing Correction at the CSO
        Hiroshige Yoshida 1997

 + Gaussian Beams and CSO Side Cab Optics: FORTRAN tools for aiding in the optical system analysis

        Chamberlin, R.A. 29th of April 1997

To date, CSO optics have been designed with the assumption that simple geometrical optics provides a \close enough" approximation for predicting how the gaussian beams from the side cab receivers will propagate through the system. Experience and calculation show that the assumptions of geometrical optics are not adequate. For example, scans across planets show that only about 54% of the 230GHz power on the sky is coupling into the main beam, and that the primary is over illuminated. Direct measurements of the beam spot size at the secondary give an edge taper of about -5.2 dB, whereas about -10 to -14 dB was the design goal. In fact, as this memo shows, the observed behavior of the 230GHz beam is predictable using simple gaussian optics, and treating the optical elements as thin lenses. To aid in the analysis, some FORTRAN programs have been developed to model the CSO optical system. The programs are described in this memo.

+ A Wide-Field Relay Optics System for the Caltech Submillimeter Observatory
        Serabyn, E. 1997, Int. J. IR & MM Waves 18, 273

+ Cassegrain Relay Optics For The CSO Chopping Secondary: Revised CSO Optics Memo #4
        Serabyn, E., 17th of  October 1995

+ CSO Chopping Secondary Motion Requirements CSO Optics Memo #1
        Serabyn, E.  3rd of January 1992

+ Surface figure measurements of radio telescopes with a shearing interferometer
        Serabyn, E., Phillips, T.G., Masson, C.R. 1991, Applied Optics, 30(10) 1227

+ A 10-Meter Telescope for Millimeter and Sub-millimeter Astronomy
        Leighton, R. 1978, Final Technical Report for NSF Grant 73-04908 California Institute of Technology

RELATED MEMO at Owens Valley Radio Observatory

+ Thermal Behavior of the Leighton 10-m Antenna Backing Structure
        Lamb, J.W. and Woody, D.P.  23rd of October 1998, Owens Valley Radio Observatory, California Institute of Technology, MMA Memo 234

One of the OVRO antennas has been instrumented with 48 thermistors on the backing structure, and the data taken over a period of more than a month with a 2 min time resolution have been analyzed. The nighttime temperature is uniform within ~2 C while temperature differences across the structure of up to 12 C are observed during the day. There is a strong inverse correlation between wind speed and temperature variance and a weaker one on the direction of the sun and wind relative to the antenna pointing direction. Structural modeling shows that pointing and focus are strongly affected, but the effect on surface rms is at the level of 10 μm. By using the temperature information to correct the pointing and focus in real time it should be possible to effect a significant improvement in performance of the antennas.

+ Design, Construction, and Performance of the Leighton 10.4-m-Diameter Radio Telescopes
        Woody, D., Vail, D., and Schaal, W.,  1994, in Proceedings of the IEEE, 82(5) 673


A broadband superconducting detector suitable for use in large arrays
        Peter K. Day, Henry G. Leduc, Benjamin A. Mazin, Anatasios Vayonakis, Jonas Zmuidzinas  23rd of October 2003

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