Spitzer Documentation & Tools
IRS Instrument Handbook

5.4  Description of Modules in the Peak-Up Cutouts Pipeline

This pipeline consists of two modules: CROPFITS and DNTOFLUX.

5.4.1             CROPFITS

The module CROPFITS (“Crop a FITS file”) creates a FITS file that is a rectangular subset of the original one. This module is used to create images of the blue and red IRS Peak-Up images contained in SL input files bcd.fits. The rectangular area to be included is defined by four parameters: “h,” “w,” “i1,” and “j1,” which are, in units of pixels, the height, width, and lower-left x-and y-coordinate of the lower-left corner of the rectangle, respectively. The coordinates are 1-indexed, meaning they are counted starting from 1.

WCS information is handled properly by this module, and the resulting files may be used in MOPEX.

This module produces the following output files:

- cropfits_b.fits and cropfits_r.fits (from bcd.fits)

- cropfits_unc_b.fits and cropfits_unc_r.fits (from func.fits); and

- mskb.fits and mskr.fits (from bmask.fits)

The files cropfits_b.fits, cropfits_r.fits, cropfits_unc_b.fits, and cropfits_unc_r.fits are not available in the Spitzer Heritage Archive, but they can be generated by running CUPID.

5.4.2             DNTOFLUX

The module DNTOFLUX is the same module referred to in the BCD pipeline (Section 5.1.3). It multiplies the input file b0_cropfits_b.fits by 0.0114 MJy/sr/electron/sec, and the input file b0_cropfits_r.fits by 0.0119 MJy/sr/electron/sec. The BUNIT header keyword is set to the new unit (MJy/sr) in the output files bcdb.fits and bcdr.fits. The uncertainty files are also processed to produce the files uncb.fits and uncr.fits.