IXPE Calibration FilesThis page contains a summary of the IXPE Calibration files which are currently in the Calibration Database (CALDB). The table links to the latest CALDB tar file and users can download it to install the IXPE CALDB locally. Instructions for installing the CALDB for IXPE or other missions are available from the CALDB Installation page. The easiest way to access calibration data for IXPE or other HEASARC-supported missions is via remote access, which allows direct access the current HEASARC CALDB without having to install any calibration data locally. Caldb access for IXPE requires the latest version of the caldb.config file (updated 20220314 or later) which is available at https://heasarc.gsfc.nasa.gov/FTP/caldb/software/tools. Please replace your current $CALDBCONFIG file with this updated version.
HISTORY of IXPE CALDB releases
Latest NewsThe IXPE Science Operations Center has begun reprocessing IXPE observations beginning with the first observation of the baseline mission, the supernova remnant Cas A (ObsID 01001301). Reprocessing will proceed chronologically through all observations taken prior to 08 April 2025. Observations made beyond that date have already been processed with the latest software version. Reprocessing often results in improved energy gain, improved aspect determination, and increased exposure times. To determine if a particular observation has been reprocessed, check, e.g., the processing date field in HEASARC's Browse interface or the DATE keyword value in the Level 2 event list files. The due date for IXPE Cycle 4 proposal submission is Sept 17, 2026. Proposals should be submitted via the HEASARC's ARK Remote Proposal System (RPS). For more information about this cycle, please visit the IXPE Cycle 4 Guide for Proposals Page. IXPE Cycle 4 proposers should note that the required one paragraph work plan has been moved to the Non-anonymized Expertise and Resources (E&R) document and should be non-anonymized. Consequently, the page limit for the E&R document has now been increased to 2 pages. For more information, please visit the Cycle 4 proposal guide. For any questions about proposal submission and guidelines, please contact the IXPE help desk. The IXPE Caldb has been updated for the GPD (version 20260610) and XRT (version 20260609). Downloads are available from the IXPE Calibration page. Users can also access the HEASARC IXPE caldb via remote access. Delivery of data from IXPE's Detector Unit 2 (DU2) has resumed. The IXPE team performed an extensive recalibration campaign including 2.7 Ms of exposure on the bright X-ray binary Cyg X-2 in December 2025 and January 2026. The recalibration has successfully restored the polarization and spectral response of DU2. All data since the anomaly in April 2025 have been reprocessed and re-delivered with DU2. Data delivery for new observations now includes DU2. Users are encouraged to compare the results obtained with the different DUs and report any significant discrepancies via the IXPE Help Desk. For more information on the anomaly, please see this presentation by the IXPE SOC. |
- HEASARC Director: Vacant
- NASA Official: Ryan Smallcomb
- Web Curator: J.D. Myers
- Last Modified: 29-Jun-2026