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                                    NUSTAR
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- Updates for NuSTARDAS 1.6.0:

  Please note that this version requires NuSTAR CALDB dated 2016
  03/15 or newer and will not work with older versions of the CALDB.

  Major changes introduced in this version:

  nusplitsc (NEW TASK):

  When the primary star tracker (also known as a camera head unit, or
  CHU) is blinded by the Earth limb or glint from the Sun the data is
  recorded in 'Mode 06' by the pipeline. In this mode the pipeline
  uses the spacecraft start rackers (CHUs 1, 2, and 3) to determine
  the sky position of each count. This sky position can be subtly
  different when different combinations of star trackers are guiding
  the observatory pointing, resulting in blurring of the output image.

  nusplitsc allows the user to generate separate independent output
  files for each CHU combination, each of which should have reduced
  blurring and higher fidelity. We note that the absolute position of
  these images may still be different than the Mode 01 data set and do
  not recommend using RA/DEC coordinates when extracting produces in
  these modes without first inspecting the images.

  See the Observatory Guide as well as Walton et al. (2016) and
  Grefenstette et al. (2016) for more details.

- nucalcsaa: The SOC has optimized new algorithms to automatically
  generate GTIs that exclude regions of the orbit that produce
  enhanced background counts in the detector.  See the Observatory
  Guide for a full description of these new modes and their effects.

- nupipeline: New options to accomodate the nusplitsc and nucalcsaa
  tasks. Added optional call to the new 'nusplitsc' module (parameter
  'runsplitsc', set to 'no' by default) and modified the call to
  'nucalcsaa' from nupipeline.

- nuflagbad: Minor bug fix to exclude hot pixels in the output
  badpixel file (nu*_bp.fits) in case of reprocessed files;

- nuscreen: Addition of a new keyword (OBSMODE) storing the NuSTAR
  observing mode to the output cleaned event files;

- nufilter: Addition of the keywords MJDREFI and MJDREFF in the
  output filter (nu*.mkf) file;

- nucoord: Value update of the RA_NOM and DEC_NOM keywords in the
  +0 and +6 extension of unfiltered event files.