Tracking the X-ray Emission of the Remarkable SGRB 211106A

The distribution of jet angles for short gamma-ray bursts (SGRBs) is critical to constrain as it directly affects the true energy scale and event rate, which is of particular interest in the midst of the new LVK run for next year. Our current knowledge of the jet angle distribution comes almost exclusively from X-ray observations at >1 day after the burst. Here, we propose for a Chandra DDT observation to continue to monitor the afterglow of SGRB 211106A and constrain its late-time collimation up to ~60 days post-trigger, either from the detection of the X-ray afterglow, which places a lower limit on the opening angle at >15 deg, or a non-detection of the afterglow, indicating a jet break has occurred and constraining the jet break to 20-25 deg. We have broad-band afterglow observations, which will be leveraged to provide the tightest constraints on the jet angle.