Last modified: 8 October 2019

URL: https://cxc.cfa.harvard.edu/ciao/caveats/acis_jupiter.html

Caveat: Uncalibrationed energy for Jupiter


The ACIS observations of Jupiter from December 2000 (OBSIDs 2398, 2399, 2400, 2401, 2407, 2408) were performed with a variety of detection thresholds for calibration purposes. As only the standard thresholds have been calibrated, the energy, and PI calculations in the L1 and L2 data products are incorrect.

In other observations (especially 2399) the standard thresholds were used, however much of the signal is due to optical light. Feel free to analyze this data but a thorough understanding of the instrument and observational setup will be necessary. Also standard CXC and CIAO tools may not be appropriate. Please direct specific questions to the CXC Helpdesk.