Holographic Measurement and Improvement of the Green Bank Telescope Surface

@article{Hunter2011HolographicMA,
  title={Holographic Measurement and Improvement of the Green Bank Telescope Surface},
  author={Todd R. Hunter and Frederic R. Schwab and Steven White and John M. Ford and Frank D. Ghigo and Ronald J. Maddalena and Brian S. Mason and John D. Nelson and Richard M. Prestage and Jason Ray and Paul A. Ries and Robert Simon and Sivasankaran Srikanth and Peter Whiteis},
  journal={Publications of the Astronomical Society of the Pacific},
  year={2011},
  volume={123},
  pages={1087 - 1099}
}
We describe the successful design, implementation, and operation of a 12 GHz holography system installed on the Robert C. Byrd Green Bank Telescope (GBT). We have used a geostationary satellite beacon to construct high-resolution holographic images of the telescope mirror surface irregularities. These images have allowed us to infer and apply improved position offsets for the 2209 actuators which control the active surface of the primary mirror, thereby achieving a dramatic reduction in the… 
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References

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TLDR
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During the design phase of the Green Bank Telescope (GBT), various means of providing an accurate surface on a large aperture paraboloid, were considered. Automated jacks supporting the primary
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We present a technique for the accurate estimation of large-scale errors in an antenna surface using astronomical sources and detectors. The technique requires several out-of-focus images of a
IMPLICATIONS OF A HIGH ANGULAR RESOLUTION IMAGE OF THE SUNYAEV–ZEL'DOVICH EFFECT IN RXJ1347−1145
The most X-ray luminous cluster known, RXJ1347−1145 (z = 0.45), has been the object of extensive study across the electromagnetic spectrum. We have imaged the Sunyaev–Zel'dovich effect (SZE) at 90
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