The Neil Gehrels Swift Observatory

Partial Coding Map for the Swift BAT Instrument

The BAT team is making available several helpful files and images to aid potential Swift users in understanding the BAT capabilities.

  1. BAT partial coding map, FITS format. The data within expresses the approximate fractional exposure as a function of position on the sky. The coordinates are sky coordinates (RA/DEC).
  2. Graphic display of the data in the above FITS file, PNG format. Partial coding contours of 10%, 50% and 100% are shown.
  3. One FITS file for each of the closed contours: 5%, 50%, and 95% partial coding.

    The FITS files contain these positions expressed in BAT tangent plane coordinates (IMX = BAT_X / BAT_Z and IMY = BAT_Y / BAT_Z), sky unit vector, and RA / DEC. For conversion to sky coordinates, a spacecraft attitude of RA = 0, DEC = 0, ROLL = 0 was used. The RA and DEC are centered on zero, so there are negative right ascensions.

    See the COMMENTs lines in the FITS files for more details.