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Title: All-weather calibration of wide-field optical and NIR surveys

The science goals for ground-based large-area surveys, such as the Dark Energy Survey, Pan-STARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a percent or better. This performance will need to be achieved with data taken over the course of many years, and often in less than ideal conditions. This paper describes a strategy to achieve precise internal calibration of imaging survey data taken in less than 'photometric' conditions, and reports results of an observational study of the techniques needed to implement this strategy. We find that images of celestial fields used in this case study with stellar densities ∼1 arcmin{sup –2} and taken through cloudless skies can be calibrated with relative precision ∼0.5% (reproducibility). We report measurements of spatial structure functions of cloud absorption observed over a range of atmospheric conditions, and find it possible to achieve photometric measurements that are reproducible to 1% in images that were taken through cloud layers that transmit as little as 25% of the incident optical flux (1.5 magnitudes of extinction). We find, however, that photometric precision below 1% is impeded by the thinnest detectable cloud layers.more » We comment on implications of these results for the observing strategies of future surveys.« less
Authors:
 [1] ; ; ;  [2] ;  [3] ;  [4] ; ;  [5] ;  [6] ;  [7]
  1. SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)
  2. National Optical Astronomy Observatory, Tucson, AZ 85718 (United States)
  3. Steward Observatory, University of Arizona, Tucson, AZ 85718 (United States)
  4. Texas A and M University, College Station, TX 77843 (United States)
  5. Department of Astronomy, University of Washington, Seattle, WA 98195 (United States)
  6. Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile)
  7. Harvard Smithsonian Center for Astrophysics, Harvard University, Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22340041
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 147; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; ACCURACY; CALIBRATION; DENSITY; IMAGES; LAYERS; NEAR INFRARED RADIATION; NONLUMINOUS MATTER; PHOTOMETRY; SKY; STRUCTURE FUNCTIONS; TELESCOPES; VISIBLE RADIATION