7.5 The ae_make_catalog Tool

The ae_make_catalog tool is run for each observation, as shown in Figure 8. It uses the source information stored in AE extraction directories (by ae_source_manager) to iteratively define non-overlapping extraction apertures for a single ObsID.¹¹This tool requires you to have set up a set of standardized paths to the input files needed by AE, as shown in the Getting Started section (3). The tool requires two parameters:
ae_make_catalog, '1875', EVTFILE\_BASENAME='spectral.evt'

• The tool uses the observation name (obsname) parameter to identify the directory ../obsXXXX/ where it expects to find various observation data products (with the standard names used by our AE recipe).
• The EVTFILE_BASENAME parameter specifies the filename for the event list (in ../obsXXXX/) from which you wish to extract spectra.

• The optional keyword parameter SRCLIST_FILENAME can be used to specify a source list other than the default, all.srclist.
• The optional keyword parameter NOMINAL_PSF_FRACTION can be used to specify a nominal PSF fraction for isolated sources other than the default, 0.90.
• The optional keyword parameter MINIMUM_PSF_FRACTION can be used to specify a minimum PSF fraction other than the default, 0.40.
• The optional keyword parameter REGION_ONLY can be used to specify that PSFs should be constructed for only the nominal energy, saving computer time.
• If the optional keyword parameter SHOW is set to zero, then the DS9 visualization normally spawned will be skipped.
• Any other keyword parameters supplied are passed on to the CONSTRUCT_REGIONS stage of AE.

Three files pertaining to the whole source list are written to the observation directory (e.g. ../obs1875/):

obs.cat

An AE catalog containing the sources observed in this ObsId, with the PSF fractions adjusted to avoid overlapping extraction regions.

extract.reg

A DS9 region file showing the positions and extraction regions for all the sources.

obs.collated

A FITS table containing preliminary source properties (§7.12) for the sources observed in this ObsId.

Since extraction regions have a minimum size (controlled by parameter NOMINAL_PSF_FRAC) very crowded sources will have overlapping regions. A measure of each source region's overlap with its neighbor is saved in the source property OVERLAP in obs.stats.