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arXiv · 1208.4672

Tests & Calibration on Ultra Violet Imaging Telescope (UVIT)

Amit Kumar·S. K. Ghosh·P. U. Kamath·Joe Postma·S. Kathiravan·P. K. Mahesh·Nagbhushana. S·K. H. Navalgund·N Rajkumar·M. N. Rao·K. S. Sarma·S. Sriram·C. S. Stalin·S. N. Tandon
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Abstract

Ultra Violet Imaging Telescope on ASTROSAT Satellite mission is a suite of Far Ultra Violet (FUV; 130 to 180 nm), Near Ultra Violet (NUV; 200 to 300 nm) and Visible band (VIS; 320 to 550nm) imagers. ASTROSAT is a first multi wavelength mission of INDIA. UVIT will image the selected regions of the sky simultaneously in three channels & observe young stars, galaxies, bright UV Sources. FOV in each of the 3 channels is about 28 arc-minute. Targeted angular resolution in the resulting UV images is better than 1.8 arc-second (better than 2.0 arc-second for the visible channel). Two identical co-aligned telescopes (T1, T2) of Ritchey-Chretien configuration (Primary mirror of 375 mm diameter) collect the celestial radiation and feed to the detector system via a selectable filter on a filter wheel mechanism; gratings are available in the filter wheels of FUV and NUV channels for slit-less low resolution spectroscopy. The detector system for each of the 3 channels is generically identical. One telescope images in the FUV channel, and other images in NUV and VIS channels. One time open-able mechanical cover on each telescope also works as Sun-shield after deployment.We will present the optical tests and calibrations done on the two telescopes. Results on vibrations test and thermo-vacuum tests on the engineering model will also be presented.

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Amit Kumar, S. K. Ghosh, P. U. Kamath, Joe Postma, S. Kathiravan, P. K. Mahesh, Nagbhushana. S, K. H. Navalgund, N Rajkumar, M. N. Rao, K. S. Sarma, S. Sriram, C. S. Stalin, S. N. Tandon. 2012-08-23. Tests & Calibration on Ultra Violet Imaging Telescope (UVIT). https://doi.org/10.1117/12.924147

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