A two-color CCD survey of the North Celestial Cap: I. The method

Evgeny Gorbikov, Noah Brosch, Cristina Afonso

Research output: Contribution to journalArticlepeer-review


We describe technical aspects of an astrometric and photometric survey of the North Celestial Cap (NCC), from the Pole (δ=90°) to δ=80°, in support of the TAUVEX mission. This region, at galactic latitudes from ~17° to ~37°, has poor coverage in modern CCD-based surveys. The observations are performed with the Wise Observatory one-meter reflector and with a new mosaic CCD camera (LAIWO) that images in the Johnson-Cousins R and I bands a one-square-degree field with sub-arcsec pixels. The images are treated using IRAF and SExtractor to produce a final catalogue of sources. The astrometry, based on the USNO-A2. 0 catalogue, is good to ~1 arcsec and the photometry is good to ~0.1 mag for point sources brighter than R=20.0 or I=19.1 mag. The limiting magnitudes of the survey, defined at photometric errors smaller than 0.15 mag, are 20.6 mag (R) and 19.6 (I). We separate stars from non-stellar objects based on the object shapes in the R and I bands, attempting to reproduce the SDSS star/galaxy dichotomy. The completeness test indicates that the catalogue is complete to the limiting magnitudes.

Original languageEnglish
Pages (from-to)203-217
Number of pages15
JournalAstrophysics and Space Science
Issue number2
StatePublished - 2010


  • Astrometry
  • Instrumentation
  • North Celestial Pole
  • Photometry
  • Survey


Dive into the research topics of 'A two-color CCD survey of the North Celestial Cap: I. The method'. Together they form a unique fingerprint.

Cite this