Results from the Image Step

After jemx_science_analysis finishes its operation, the results are stored separately for each ScW of the observation group. They are located in the subdirectories named scw/RRRRPPPPSSSF.001/ (where RRRRPPPPSSSF is the number of the ScW).

Go to one of these directories and have a look at the files

cd scw/010200210010.001/
ls

This is the output from all the processing steps done by the script.

The output image is jmx2_sky_ima.fits. You can check it using e.g. fv:

fv jmx2_sky_ima.fits

You will find that this file contains 7 extensions: the index of all images, 3 cleaned sky images (RECONSTRUCTED type), and 3 variance maps, one for each of the 3 selected energy bands (see Fig. 11).

Figure 11: The content of jmx2_sky_ima.fits file.

In the file jmx2_srcl_res.fits you find a list of all found sources, the energy bands, and the derived flux values, and in the file jmx2_srcl_cat.fits the list of the sources in the input catalog. You can see that most of the catalog sources were not found, as they are too weak. When you run the lightcurve and spectra extraction steps the results would be produced for all sources listed in jmx2_srcl_res.fits.

Since OSA10 images are produced with counts per cm . With OSA10.1 source spectra and lightcurves show countrates per unit of detector area, in agreements with OGIP standards requirements. To extract the correct source fluxes it is fundamental to use OSA10.1 with the latest available IC files.

There is a nice way to locate the found sources as well as the catalog sources on the sky image. To do it use the utility cat2ds9:

cat2ds9 jmx2_srcl_res.fits\[1] found.reg symbol=box color=red
cat2ds9 jmx2_srcl_cat.fits\[1] cat.reg symbol=circle color=white

(to find out more about this program type cat2ds9 -h in the command line). With the help of the above two commands the two files found.reg and cat.reg are created. They contain the lists of all the found sources and all the catalog sources, respectively.

With the help of ds9 viewer you can display the sky images in any of the avilable energy bands. For example, to look at the 7-11 keV image which (if you used the option IMA_detImagesOut=yes) is contained in the 5th extension of the jmx2_sky_ima.fits file you can type

ds9 jmx2_sky_ima.fits\[5]

You can load the region files cat.reg and found.reg created with cat2ds9 by using the ``Region'' menu of ds9 or directly from the command line:

ds9 jmx2_sky_ima.fits\[5] -region cat.reg

In Fig. 12, the left panel shows the Crab region in the second energy band (7-11 keV) with the catalog sources, and the right one - the same region with the found sources (Science Window 010200210010).

Figure 12: The image of Crab region. Catalog sources in the FOV are shown with white circles. The only found source (Crab) is shown with a red box.