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MERGE_IMAGE

Purpose: To combine all of the count (counts_n.fits), modelled background counts (back_n.fits and off_n.fits), exposure map (expose_n.fits), and mask (usually just the exposure map) into final surface-brightness (count rate and count-rate uncertainty) images. Nearly the same as FINAL_IMAGE but runs on mosaic images.

File Input:
1) Other fixed input - after the band range has been selected, the counts_n.fits, back_n.fits, off_n.fits, and expose_n.fits for the bands ``n'' (counts.fits, back.fits, off.fits, and expose.fits for HRI data.)

Interactive Input:
1) Band range - the range of bands to be combined for the final image (i.e., ``2 2'' will produce band R2, ``4 5'' will produce band R45 as a 3/4 keV band, and ``8 2'' will produce band R1L2, ``4 7'' will produce band R47 combining the bands R4, R5, R6, and R7). Enter ``0 0'' for HRI data.
2) Fractional limit for template - of use when the exposure maps are being used for masking. The average value of the mask is determined using all values greater than zero, then all pixels where the mask values is less than the scale factor multiplied by the average value are excluded. A limit of 0.02 is reasonable in most cases. 3) Mask image - enter image to use as a mask. Enter the ``expose'' map to use the exposure map for the masking.

Image Output:
Fits files of the mosaic count-rate and count-rate-uncertainty. The files rate_n.fits and sig_n.fits (where n is the band number or band range) contain count rate and count-rate uncertainty (in units of counts s  arcmin ) for the full image.