CALTECH SUBMILLIMETER OBSERVATORY
TECHNICAL MEMO 
+ 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
Abstract:
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
Abstract:
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)
Abstract:
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
Abstract:
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
Abstract:
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
REFEREED
TECHNICAL PAPERS
+ 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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