Results of the initial calibration of the Ultra-Violet Imaging Telescope (UVIT) were reported earlier by Tandon et al. (2017). The results reported earlier were based on the ground calibration as well as the first observations in orbit. Some additional data from the ground calibration and data from more in-orbit observations have been used to improve the results. In particular, extensive new data from in-orbit observations have been used to obtain (a) new photometric calibration which includes (i) zero-points (ii) flat fields (iii) saturation, (b) sensitivity variations (c) spectral calibration for the near Ultra Violet (NUV; 2000 - 3000 Angstroms) and far Ultra-Violet (FUV; 1300 - 1800 Angstroms) gratings, (d) point spread function and (e) astrometric calibration which included distortion. Data acquired over the last three years show continued good performance of UVIT with no reduction in sensitivity in both the UV channels.
@article{arxiv.2002.01159,
title = {Additional Calibration of the Ultra-Violet Imaging Telescope on board AstroSat},
author = {S. N. Tandon and J. Postma and P. Joseph and A. Devaraj and A Subramaniam and I. V. Barve and K. George and S. K. Ghosh and V. Girish and J. B. Hutchings and P. U. Kamath and S. Kathiravan and A. Kumar and J. P. Lancelot and D. Leahy and P. K. Mahesh and R. Mohan and S. Nagabhushana and A. K. Pati and N. Kameswara Rao and K. Sankarasubramanian and S. Sriram and C. S. Stalin},
journal= {arXiv preprint arXiv:2002.01159},
year = {2020}
}
Comments
15 pages, 8 figures, Accepted for publication in Astronomical Journal