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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').

8 results found.

  1. GRB 230802A: Fermi GBM observation
  2. GRB 230802A: Swift-BAT refined analysis
  3. GRB 230802A: Swift/UVOT Upper Limits
  4. Swift GRB 230802A: Global MASTER-Net observations report
  5. GRB 230802A: BOOTES-5/JGT optical upper limit
  6. GRB 230802A: Swift-XRT refined Analysis
  7. GRB 230802A: Enhanced Swift-XRT position
  8. GRB 230802A: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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