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Purpose: To combine all of the count, modelled background counts, exposure map, and mask into final surface-brightness images. If a mask was used in RATE and CAST_SSX, it need not be used here.
1) Observation data set fits files - none
2) Other fixed input - after the band has been selected, the program reads in the appropriate cast count (b_n.fits), background (ssx_n.fits, lte_n.fits, partin.fits, partex1.fits, partex2.fits, and partap.fits), and exposure (expose_n.fits) maps. A mask is also used. This can either be the exposure map if the entire field is desired or an added selection such as the point-source mask created by the program DETECT.
1) PSPC detector selection - 1 for PSPC C, 2 for PSPC B.
2) Gain control - 1 for high gain, 2 for low gain.
3) 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 covering bands R4, R5, R6, and R7).
4) Afterpulse control - 1 to add the afterpulse component, 0 not to. This parameter is only queried for if the R1 or R1L band is used.
5) Mask image - enter image to use as a mask. Enter a carriage return to use the exposure map.
A QDP file, radial_n.qdp where n is the band or band range, is also produced of the radial profile of the image. The utility of the radial profile depends upon the intrinsic structure of the field and the removal of point sources. For instance, the 1/4 keV band radial profile of the M101 image after point-source exclusion is sharply peaked at the center, and flat for off-axis angles greater than . The flat part of the distribution indicates the surface brightness of the cosmic background plus residual LTE contamination.
Average count rate and count rate uncertainty for the selected (unmasked) region of the image. This count rate derived with a completely unmasked (exposure map entered as the mask in input 5) above) can be compared to the all-sky survey value to determine an estimate of the level of the residual long-term enhancement contamination.
Fits files of the final images, particle background, and total non-cosmic background (for use in the adaptive filter smoothing program ADAPT). The files rate_n.fits and sig_n.fits (where n is the band number or range) contain count rate and count rate uncertainty (in units of counts s arcmin ) for the full image. The files rate_bin_n.fits and sig_bin_n.fits contain the same thing except that the data have been binned by 16 in each dimension. The file part_n.fits contains the particle background and the file back_n.fits contains an image of the total background counts.