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Purpose: To cast the modelled scattered solar X-ray background and long-term enhancement background into sky coordinates. Since the long-term enhancement background apparently originates as a flat field and is vignetted, the modelled counts derived by the programs RATE_FIT and LTE are distributed in sky coordinates by a scaling of the cast exposure map. The scattered solar X-ray background is treated in a similar manner but with the additional complication that the distribution must be appropriately ``tilted'' (Snowden and Freyberg 1993). Note that the exposure map for the chosen band is always used for the long-term enhancement component but that the exposure map for band R4 is used for the R5 and higher bands (the counts for band R7 can safely be set to zero). This is because while the counts may be found in the bands R5 and R6, they originate as 0.53 keV X-rays and therefore are vignetted more like X-rays in the R4 band. Vignetting is an energy rather than pulse-height dependent effect. If masking was used in while running RATE, then the same mask must be used here.
File Input:
1) Observation data set fits files - none
2) Other fixed input - after the band has been selected, the program
reads in the appropriate cast exposure maps.
3) Mask - same as used in RATE.
Interactive Input:
1) Band to be cast - 1-8 for bands R1-R7 and where 8 refers to band
R1L.
2) Scattered solar X-ray parameters - counts, angle, and gradient from
program TILT.
3) LTE counts - net counts from program LTE.
4) Mask control - 1 for masking, 0 for no masking. If masking is chosen,
the program will next query for the mask name.
4a) Mask name - name of fits file containing mask.
Image Output:
Fits files of the cast LTE and SSX modelled background counts
(lte_n.fits and ssx_n.fits where n is the band number).