NExScI Keck Interferometer Data Memos Page

As part of the evaluation of the visibility mode data, NExScI has produced the following data memos which describe in detail some of the data calibration and verification tests. These memos are intended to help users understand the accuracy and systematics in KI visibility data.

  • Clock memo describing clocking problem affecting data from June 2002 to June 2003 and efforts to correct the data (best viewed in color).
  • Jitter memo describing the jitter correction and the basis for our recommendation to NOT use this option in the wbCalib/nbCalib data calibration.
  • Ratio memo describing the ratio correction and showing the data supporting our recommendation to use the ratio correction in the wbCalib/nbCalib data calibration.
  • Recommended settings memo describing the data used to determine the data averaging times and calibration method used in the standard Kvis processing to Level 1 data. Updated for flux bias (see flux bias memo below).
  • Flux bias memo quantifying the observed bias in the measured visibility with target flux. A correction has been implemented as part of the wbCalib/nbCalib package and the memo describes the on-sky verifications performed. The KI team recommends using this correction if the target and calibrator K band fluxes are different by more than 0.2 mags.

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