### 4 Running SExtractor

A native, FITS-only, version of SExtractor is also distributed with the EXTRACTOR package for convenience and use in the object detection toolbox in the GAIA application. The executable image is installed in $EXTRACTOR_DIR and is ran as described in the SExtractor User’s Guide(MUD/165). To use this version either put $EXTRACTOR_DIR on your PATH or define an alias:

% alias sex \$EXTRACTOR_DIR/sex

then type:

% sex image [-c configuration-file] [-Parameter1 Value1] [-Parameter2 Value2] ...

Note that if the -c option is omitted, file default.sex in the current working directory will be used – if you want to use the installed default file, you will need to specify it explicitly.