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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

6 results found.

  1. GRB 230322B: Swift-BAT refined analysis
  2. GRB 230322B: Swift/UVOT Detection
  3. GRB 230322B: Swift-XRT refined Analysis
  4. GRB 230322B: Enhanced Swift-XRT position
  5. Swift GRB 230322B: Global MASTER-Net observations report
  6. GRB 230322B: Swift detection of a burst with optical counterpart


Download all Circulars as a .tar.gz archive:
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