Calibration and performance of the photon-counting detectors for the Ultraviolet Imaging Telescopes (UVIT) of the Astrosat observatory

Abstract

We describe calibration data, and discuss performance of the photon-counting flight detectors for the Ultraviolet Imaging Telescopes on the Astrosat observatory. The paper describes dark current, flat field and light-spot images for FUV, NUV, and Visible band detectors at more than one wavelength setting for each. We also report on nominal gain and low-gain operations, full- and sub-window read rates, and non-photon-counting modes of operation, all expected to be used in flight. We derive corrections to the event centroids from the CMOS readout arrays, for different centroid algorithms. We derive spatial resolution values for each detector and plots of point-source signal saturation for different flux levels. We also discuss ways to correct for saturation in extended object images.

27 pages, including 4 tables. 14 Figures. To be published in PASP

References in corpus (4)

• The On-Orbit Performance of the Galaxy Evolution Explorer
• Paper II: Calibration of the Swift ultraviolet/optical telescope
• The measurement errors in the Swift-UVOT and XMM-OM
• Studying the Imaging Characteristics of Ultra Violet Imaging Telescope (UVIT) through Numerical Simulations

Cited by in corpus (20)

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• Ultra Violet Imaging Telescope (UVIT) on ASTROSAT
• In-orbit Performance of UVIT and First Results
• In-orbit Performance of UVIT on ASTROSAT
• Investigating the In-Flight Performance of the UVIT Payload on ASTROSAT
• UVIT imaging of WLM : Demographics of star forming regions in the nearby dwarf irregular galaxy
• Tracing young star-forming clumps in the nearby flocculent spiral galaxy NGC 7793 with UVIT imaging
• The AstroSat UV Deep Field North: the far and near ultraviolet photometric catalog
• Understanding the secular evolution of NGC 628 using UVIT
• UVIT view of dwarf irregular galaxy IC 2574 : Is the star formation triggered due to expanding H I shells?
• Curvit: An open-source Python package to generate light curves from UVIT data
• A Stellar Population Synthesis Model for the Study of Ultraviolet Star Counts of the Galaxy
• UVIT Study of the MAgellanic Clouds (U-SMAC) II. A Far-UV catalog of the Small Magellanic Cloud: Morphology and Kinematics of young stellar population
• Dorado and its member galaxies. III. Mapping star formation with FUV imaging from UVIT
• New Results from the UVIT Survey of the Andromeda Galaxy
• A tale of two nearby dwarf irregular galaxies WLM and IC 2574 -- as revealed by UVIT
• Calibration of VELC detectors on-board Aditya-L1 mission
• Dorado and its member galaxies II. A UVIT picture of the NGC 1533 substructure
• Results from AstroSat LAXPC Observations of Hercules X-1 (Her X-1)
• JUDE: An Ultraviolet Imaging Telescope Pipeline