Autor: |
Jamie Cookson, Peter A. R. Ade, Carole Tucker, Rashmikant V. Sudiwala, Dan Bintley, Shaoliang Li |
Rok vydání: |
2018 |
Předmět: |
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Zdroj: |
Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX. |
Popis: |
SCUBA-2 is a world leading wide field submillimeter camera on the JCMT with two, large format background limited TES arrays, which are used to image simultaneously in the 450μm and 850um atmospheric windows. SCUBA-2 has been producing excellent science for over 6 years however, as we reported previously, excess in-band power loading of the arrays is a concern. One possibility that we considered was that the currently installed hot-pressed filters at the 4K stage were being warmed significantly above 4K by incoming infrared radiation. In an attempt to reduce the power loading we cryogenically tested a new 60K filter stack that incorporated a redesigned thermal blocking filter. A direct comparison was then made to the performance of the existing 60K filter stack installed in SCUBA-2. We saw a tremendous improvement in the infrared rejection with the new design and proceeded to install the new filter stack into SCUBA-2. In this paper, we describe the testing and installation of the new and improved design of thermal blocking filter into the instrument and report the resulting performance change based on data from the first 12 months of science operation with the new filters. We also present the combined filter bandpass profiles as measured in-situ with FTS-2. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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