For the community

X-IFU response matrices (2026) – last update : May 2nd, 2026

Following the reformulation of the NewAthena mission, a new set of X-IFU resources is now available for download at the link below. Check the INSTRUCTIONS.README file for a description of the response files distributed. The files are intended to be used for the mission adoption, the red book and the newAthena special issue.

Mirror resource products for the baseline mission configuration are available from :https://www.cosmos.esa.int/web/athena/resources-by-esa

As of March 2024, the X-IFU team considers a mirror of 13 rows as the baseline and an instrument spectral resolution of 4 eV. However, we wish to keep an X-IFU internal goal design of 3 eV. Thus we also release response files with 3 eV, understanding that this is not the baseline.

You will find information on the instrument efficiency assumed in generating these response files in Barret et al. (Experimental Astronomy, 2023) and Peille et al. (Experimental Astronomy, 2025). Please refer to this paper if you intend to use those response files in your work. Thanks !

Download the whole set of arf, rmf and SIXTE files with the relevant documentation in one big zip file

X-IFU non X-ray background files (2026)

The X-IFU non X-ray background files were originally produced by the IAPS/INAF group led by Simone Lotti. They are provided for different extraction regions. See the INSTRUCTIONS.README for use. Please see Lotti et al. (The Astrophysical Journal, 2021) for a review of the X-IFU particle background.

Click here to download the background files