During the last week the observing schedule was interrupted due to high radiation associated with solar activity. The loads were halted at 10:18pm EST on Feb 26 through a ground command to execute the SI Safing SCS 107. This ensured that the accumulated radiation dose for ACIS remained below the allowed threshold. All spacecraft actions were nominal. A related real-time procedure was executed Feb 27 to update the observation identifier number to aid CXCDS processing. Loads for a replanned schedule were uplinked on Mar 1 with about 110ks of science time lost. Planned observations which were impacted by the interruption will be rescheduled in future weeks.

Real-time procedures were executed on Mar 1 to perform a routine self-check of the Electrical Interface Assembly (EIA) Sequencer, to perform a diagnostic dump of the Control Processing Electronics (CPE) and to patch the CPE Yaw bias to zero for use in safe mode.

Preparations were completed for the Spring 2023 eclipse season; the season contains 25 eclipses and runs from Feb 25 to Apr 30. Real-time procedures were executed on Feb 24 to prepare for the first eclipse by dumping and clearing the EPS glitch counters and activating SCS 29. Chandra passed through the 1st, 2nd and 3rd eclipses of the season on Feb 25, Feb 28, and Mar 3 respectively, with nominal power and thermal performance.

A Chandra image release was issued on Feb 28 describing observations of the Tycho supernova remnant by Chandra and the Imaging X-ray Polarimetry Explorer (IXPE). A thin line around the outside of the supernova remnant, seen in the Chandra data, shows where electrons have been accelerated to high energies by spiraling around magnetic fields lines and producing X-rays. This provides evidence that supernova remnants are a major source of energetic particles. For details see: https://chandra.si.edu/photo/2023/tycho/