Abstract
Ultraviolet Imaging Telescope (UVIT) is one of the payloads onboard AstroSat, India’s first multi-wavelength Astronomy mission. UVIT is primarily designed to make high resolution images in wide field, in three wavelength channels simultaneously: FUV (130–180 nm), NUV (200–300 nm) and VIS (320–550 nm). The intensified imagers used in UVIT suffer from distortions, and a correction is necessary for these to achieve good astrometry. In this article we describe the methodology and calculations used to estimate the distortions in ground calibrations.
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References
Agrawal, P.C., ASTROSAT Collaboration: The Indian multiwavelength astronomy satellite AstroSat. Bull. Astron. Soc. India 33, 351–351 (2005)
Archna, S., Rai, S.K., et al.: X-ray characterization of thin foil gold mirrors of a soft X-ray telescope for AstroSat. Exp. Astronomy 28, 11 (2010)
Kumar, A., Ghosh, S.K., et al.: Tests and calibration on ultra violet imaging telescope (UVIT). Proc. SPIE, 8443 (2012)
Annapurni, S., Tandon, S.N., et al.: A hot companion to a blue straggler in NGC188 as revealed by the ultra-violet imaging telescope (UVIT) on ASTROSAT (2016)
GALEX: Summary of changes for GALEX ops7 pipeline (2010). http://www.galex.caltech.edu/researcher/gr6_docs/GI_Doc_Ops7_19mar2010.pdf
Girish, V., et al.: Verification of distortion of detectors in UVIT onboard Astrosat observatory using onboard data, In preparation (2016)
Jones, E., Oliphant, E., Peterson, P., et al.: Scipy: Open source scientific tools for python (2001). http://www.scipy.org/
Landsman, W.B.: The IDL astronomy user’s library, A.S.P. Conference Series. In: Hanisch, R. J, Brissenden, R. J. V., Barnes, J. (eds.) Astronomical Data Analysis Software and Systems II, vol. 52, p 246 (1993)
Morrissey, P., Conrow, T., et al.: The calibration and data products of GALEX. ApJS 173, 682–697 (2007)
Ramadevi, M.C., et al.: Early in-orbit performance of Scanning Sky Monitor onboard AstroSat, submitted to Journal of Astrophysics & Astronomy (2016)
Gupta, R., Burse, M., Das, H.K., Kohok, A., Ramprakash, A.N., Engineer, S., Tandon, S.N.: IUCAA 2 meter telescope and its first light. Bull. Astron. Soc. India 30, 785 (2002)
Singh, K.P., Tandon, S., et al.: AstroSat Mission. Proc. SPIE, 9144 (2014)
Stetson, P.B.: DAOPHOT - A computer program for crowded-field stellar photometry. PASP 99, 191–222 (1987)
Acknowledgments
The authors would like to thank University of Calgary for providing the grid, IUCAA for providing the IFOSC images of mask/grid, staff of MGKM laboratory for support for IIA images taken with the CPUs and collegues of UVIT instrumentation team for all the necessary help. VG would like to thank Dr Annadurai, Director, ISRO Satellite Centre (ISAC) and Dr Anil Aggrawal, Group Director, SAG, ISAC and Dr Sreekumar, Director, IIA (former GD, SAG, ISAC) for all their encouragement and support.
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Girish, V., Tandon, S.N., Sriram, S. et al. Mapping distortion of detectors in UVIT onboard AstroSat observatory. Exp Astron 43, 59–74 (2017). https://doi.org/10.1007/s10686-016-9520-3
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DOI: https://doi.org/10.1007/s10686-016-9520-3