Lightcurve Extraction

After you have done the spectral extraction, you may want to produce a lightcurve for the same sources. Stay in the working directory $REP_BASE_PROD/obs/isgri_gc and call the ibis_science_analysis script again. On the main GUI window (see Figure ), change both Start Level and End Level to LCR, and press the ISGRI SPE and LCR button. The GUI shown in Figure will appear.

Note that to extract the lightcurve for a source you need the Pixel Illuminated Fraction (PIF) map. Such a map is created during the spectral step that we have just run. This means that at this stage you can extract the lightcurve only of the sources for which a spectrum has been created already. So leave SCW2_cat_for_extract to point to your specat.fits.

By default, for each source from the input catalog (specat.fits in our example), four lightcurves (in 20-40, 40-60, 60-100, and 100-200 keV energy bands) with 100 sec time bins will be created. You can change these values in the GUI.

The lightcurve extraction is performed by building shadowgrams for each time and energy bin. Hence this step is quite consuming in processing time and disk space. Note that due to CFITSIO limitations, the product of number of energy bins by number of time bins in a ScW should be less than 250.

Press Ok, the window will disappear and you are back to the main GUI page. Press Run.