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Thirty Meter Telescope site testing system

Skidmore, Warren and Schöck, Matthias and Tokovinin, Andrei and Djorgovski, George and Walker, Alistair and Blum, Robert and Travouillon, Tony and Seguel, Juan and Bustos, Edison and Walker, David and Vasquez, Joselina and Gillett, Paul (2004) Thirty Meter Telescope site testing system. In: Ground-based Telescopes. Proceedings of SPIE. No.5489. Society of Photo-optical Instrumentation Engineers (SPIE) , Bellingham, WA, pp. 154-164. ISBN 9780819454218.

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The Thirty Meter Telescope (TMT) site testing team are developing a suite of instruments to measure the atmospheric and optical characteristics of candidate TMT sites. Identical sets of robotically operating instruments will be placed at each candidate site. The fully developed system will comprise of a combined MASS/DIMM. a SODAR, tower mounted thermal probes and a portable DIMM. These instruments have overlapping altitude coverage and provide a measure of the C^2_n profile from the ground up with sufficient resolution to make conclusions about the ground layer and high altitude turbulence characteristics. The overlapping altitude coverage is essential to ensure consistency between these very different instruments. In addition to checking for consistency in the overlap regions, procedures are being used to cross check between instruments, i.e. the calculation of the isoplanatic angle from both the MASS and DIMM and that the integrals of the C^2_n profiles from the MASS, SODAR and 30m tower gives the same r_0 value as measured by the DIMM. We discuss a variation of the traditional DIMM system in which we employ a continuous drift mode readout technique giving a maximum of nearly 300 samples per second. Findings of our major equipment testing campaigns and first field deployment are presented that demonstrate our progress in developing a rigorous approach to site testing.

Item Type:Book Section
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Djorgovski, George0000-0002-0603-3087
Additional Information:© 2004 Society of Photo-optical Instrumentation Engineers. The Thirty Meter Telescope (TMT) Project is a partnership of the Association of Universities for Research in Astronomy (AURA), the Association of Canadian Universities for Research in Astronomy (ACURA), the California Institute of Technology and the University of California. The partners gratefully acknowledge the support of the Gordon and Betty Moore Foundation, the US National Science Foundation, the National Research Council of Canada, the Natural Sciences and Engineering Research Council of Canada, and the Gemini Partnership. We thank the many personnel, particularly the CTIO staff, that have assisted with the development and deployment of the TMT site testing equipment and whose help has been and will continue to be vital for this project.
Group:Thirty Meter Telescope
Funding AgencyGrant Number
Association of Universities for Research in Astronomy (AURA)UNSPECIFIED
Association of Canadian Universities for Research in Astronomy (ACURA)UNSPECIFIED
University of CaliforniaUNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
National Research Council of CanadaUNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Gemini PartnershipUNSPECIFIED
Subject Keywords:Site testing, DIMM, MASS, SODAR, microthermal probes, seeing, atmospheric turbulence
Series Name:Proceedings of SPIE
Issue or Number:5489
Record Number:CaltechAUTHORS:20181219-142606813
Persistent URL:
Official Citation:Warren Skidmore, Matthias Schock, Andrei A. Tokovinin, George Djorgovski, Alistair R. Walker, Robert D. Blum, Tony Travouillon, Juan Seguel, Edison E. Bustos, David Walker, Joselina Vasquez, Paul E. Gillett, "The Thirty Meter Telescope site testing system," Proc. SPIE 5489, Ground-based Telescopes, (28 September 2004); doi: 10.1117/12.549384
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91921
Deposited By: Tony Diaz
Deposited On:19 Dec 2018 22:34
Last Modified:03 Oct 2019 20:39

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