In addition to the standard HEASoft FTOOLs there is also user-contributed software which has been produced by the community. We note that this software is provided on an "As Is" basis, and that is the responsibility of the individual developers to maintain the software and to fix any bug reports, not the HEASARC's or the IXPE project's. Questions about these software packages should be directed to the developer, and not to the IXPE or HEASARC helpdesks.

• ixpeobssim: ixpeobssim is a simulation and analysis framework specifically developed for IXPE. Given a source model and the response functions of the telescopes, it is designed to produce realistic simulated observations, in the form of event lists in FITS format, containing a strict superset of the information included in the publicly released IXPE data products. The software documentation for ixpeobssim is available here, and it can be installed following the instructions provided here. If you are interested in contributing to the code development, you can follow the instructions here. For any unknown problems related to the code, we encourage the users to open a new issue on the Github page here.


• filter_background.py is a simple to use, stand-alone, tool to reject particle background following the prescription described in Di Marco, et al. AJ 165, 143 (2023). Given a Level 2 event list and its corresponding Level 1 file(s), the tool can be used to create a new Level 2 file that either removes events identified as background events, keeps only events identified as background events, or adds a new column that flags each event as either being background (particle) or non-background (X-ray) events. The tool is available on Github.