VARMOSAIC (Mar2004) ftools.integral VARMOSAIC (Mar2004) NAME varmosaic -- Make mosaic images from the deconvolved coded mask images with weights of variance USAGE varmosaic filelist outimage DESCRIPTION varmosaic is used to make mosaic images from the deconvolved sky images of the coded mask instruments with proper weights of variance. In general, coded mask sky images are accompanied by variance maps. When "varmosaic" calculate mosaic images, the following calculation is made: flux_mosaic = Sigma_i (f_i/V_i)/Sigma_i (1/V_i) Var _mosaic = 1//Sigma_i (1/V_i) where Sigma_i is summation over images, f_i and V_i are flux and variance of the i-th image, respectively. Then f_mosaic/sqrt(V_mosaic) gives the so-called significance map, which is also calculated. varmosaic is primarily designed to combine INTEGRAL ISGRI and JEMX images from many pointings ("Science Windows" in INTEGRAL terminology). Those individual Science Window images may be created by running INTEGRAL Off-line Analysis Software (OSA), or, for standard energy ranges and Good Time Intervals, can be obtained from ISDC archives at ftp://isdcarc.unige.ch/arc/rev_2/obs_isgri/RRRR.002/ssii_RRRR????????/scw for ISGRI or ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/RRRR.002/ssj1_RRRR????????/scw for JEMX1 or ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/RRRR.002/ssj2_RRRR????????/scw for JEMX2, where RRRR is a four digit Revolution number, ???????? is an eight digit Science Window number. Note, ftools/cfitsio has a capability to read remote files directly via Internet. Consequently, you may specify ScW sky images at ISDC anonymous ftp area directly in the "filelist" parameter. See an example below. PARAMETERS filelist (string) ASCII file of the input FITS file images. outimage (string) Output mosaic FITS image file name. For each energy band in the input Science Window images, the mosaic significance map, the intensity map and the variance map are calculated. In addition, the exposure map is calculated. The output file has the following structure: Primary -- 1st energy band Singicance image 1st ext -- 1st energy band Flux image 2nd ext -- 1st energy band Variance image 3rd ext -- 2nd energy band Singicance image 4th ext -- 2nd energy band Flux image 5th ext -- 2nd energy band Variance image 6th ext -- 3rd energy band Singicance image ...... Last ext -- Exposure map pixdivide (integer) The input image pixel is divided into pixdivide x pixdivide subpixels when projected on the mosaic image. outimagesize (integer) Output image pixel size. If zero, the output image size is calculated to cover all the input images. ra_ref (double) When outimagesize > 0, the RA of the reference point. If Outimagesize=0, calculated from the input images. dec_ref (double) When outimagesize > 0, the DEC of the reference point. If Outimagesize=0, calculated from the input images. clobber (yes/no) Clobber the output image file or not. EXAMPLES 1. varmosaic filelist=imagelist outimage=out.fits Create the mosaic image "out.fits" from the input file list "imagelist". Content of the imagelist is as follows: /home/ebisawa/INTEGRAL_ARCHIVES//REV0037_4U1630-47/scw/003700020010/ibis/res/isgri_sky_ima.fits /home/ebisawa/INTEGRAL_ARCHIVES//REV0037_4U1630-47/scw/003700030010/ibis/res/isgri_sky_ima.fits /home/ebisawa/INTEGRAL_ARCHIVES//REV0037_4U1630-47/scw/003700040010/ibis/res/isgri_sky_ima.fits /home/ebisawa/INTEGRAL_ARCHIVES//REV0037_4U1630-47/scw/003700050010/ibis/res/isgri_sky_ima.fits /home/ebisawa/INTEGRAL_ARCHIVES//REV0037_4U1630-47/scw/003700060010/ibis/res/isgri_sky_ima.fits The output image size and reference point are calculated automatically from the input images. 2. varmosaic filelist=imagelist outimage=out.fits outimagesize=500 ra_ref=250.0 dec_ref=-50.0 Same as above, but output image size is 500x500 pixels, and the reference point is (250.0, -50.0). 3. Now we have the "imagelist" as folllows: ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500480010/scw/005500480010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500490010/scw/005500490010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500500010/scw/005500500010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500510010/scw/005500510010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500520010/scw/005500520010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500530010/scw/005500530010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500540010/scw/005500540010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500550010/scw/005500550010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500560010/scw/005500560010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500570010/scw/005500570010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500580010/scw/005500580010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500590010/scw/005500590010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500600010/scw/005500600010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500610010/scw/005500610010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500620010/scw/005500620010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500630010/scw/005500630010.001/jmx2_sky_ima.fits.gz ftp://isdcarc.unige.ch/arc/rev_2/obs_jmx/0055.002/ssj2_005500640010/scw/005500640010.001/jmx2_sky_ima.fits.gz These are the JEMX2 images from 17 Science Windows in Revolution 55, GCDE observation, in the public archives at ISDC. Then varmosaic directly will access these remote files, and create a mosaic image. In this manner, you do not have download individiaul Science Window images. BUGS Not tested yet for images besides INTEGRAL ISGRI and JEMX. All the Science Window images are assumed to have the same structure, such that they have the same number of energy bands. Instrument specific background correction and vignetting correction are not taken into account. To handle these instrumental issues, use INTEGRAL specific tools provided by ISDC. SEE ALSO fovdsp to display the INTEGRAL field of view and INTEGRAL reference catalog sources. CONTACT ADDRESS: Ken Ebisawa code 662, NASA/GSFC Greenbelt, MD 20771, USA ebisawa@milkyway.gsfc.nasa.gov