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Extraction and Calibration

aXe Reduction Methodology in a Nutshell

The aXe reduction tasks enable automated, efficient extraction of thousands of spectra from slitless spectral images. The software drives the spectral extraction based on two sets of information:

aXe is not instrument specific, and can accommodate data from different instrument/grism combinations by specifying the required parameters in the configuration file.

Software Access

aXe is PyRAF/IRAF software which is comprised of several tasks and is distributed as a subpackage of the Space Telescope Data Analysis System (STSDAS) under analysis.slitless.axe. New releases of STSDAS become available approximately twice a year. More frequent updates and bug fixes are available in IRAFX, the development version of STSDAS, which is released weekly.

Download and installation information for the STSDAS package can be found at STSDAS Home, and for IRAFX at

Detailed notes on aXe releases and bugs can be found here.
Support of processing with AstroDrizzled products is currently provided only in versions of aXe in IRAFX with release dates after 2013-03-28.


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